BusinessFixed price vs T&M contract or maybe mixed model in software development

Many companies prefer to cooperate with external partners. Let's assess the fixed price vs t&m models of cooperation.
Updated at12.03.2024
Published at23.02.2023
Matt Sadowski
Matt Sadowski

CEO @ Custom Software Development Expert

Stanislav Naborshchikov
Stanislav Naborshchikov

Solutions Specialist

Table of contents

  1. Introduction
  2. The essence of the MIX model
  3. Conclusion
  4. Exploring the Business Facets of Software Development

Share the article


When starting custom software development or seeking information systems support, numerous medium and small businesses prefer teaming up with outside partners using contracts. They consider the advantages and disadvantages of fixed price and time and materials software agreements. Such an approach not only obviates the need to maintain an in-house team of IT experts but also streamlines the complexities involved in cost management. This way, businesses can anticipate costs more clearly, allocate their internal resources towards their core competencies, and infuse their projects with a fresh perspective and cutting-edge technologies by external specialists.

The essence of the Time and Materials price contract

The model assumes hourly payment for the work of attracted specialists. The customer pays for the result based on the labor costs of software development. The estimate of the scope of work and the timing of the project is made only roughly. At T&M pricing, changes in requirements and product design are often made, and the main thing is the result and quality of the final product, not the price and timing.

time and material contract for software project

Interim Deadlines

In contrast to fixed-price models, which usually set one deadline for the entire project, the time and materials (T&M) contract breaks the work into shorter, more manageable phases, often lasting 2-4 weeks. For each step, specific goals and deliverables are outlined. This phased approach ensures consistent progress monitoring, and at the end of each period, a detailed report is compiled to assess the accomplishments and any adjustments required for subsequent stages.

Payment for Labor Costs

Central to the time and materials contract is its flexibility in billing based on actual labor hours consumed. Clients are billed based on the hourly rate of the involved professional. This approach directly ties the payment to the work hours invested by the development or IT team. Whether it's developers, designers, or testers, their hourly rates factor into the total cost. This granular billing provides transparency, allowing clients to understand precisely where and how their investment is utilized.

Adaptability to Changes

Given its periodic review structure, the time and materials contract offers greater flexibility to make mid-course corrections. If the project's scope needs to pivot or be altered due to evolving requirements or unforeseen challenges, the model can accommodate this without requiring a complete contract overhaul.

Transparency and Collaboration 

Regular check-ins and stage-end reports foster a transparent environment. They keep the client in the loop and encourage a collaborative relationship where feedback is continually integrated, ensuring that the project remains aligned with the client's vision. Both parties share the risks since the work is assessed and billed in intervals. The software house commits to meeting the agreed-upon objectives for each phase of the project, while the client actively monitors progress to ensure the project stays on course.

Cost Predictability for Each Stage

Even though the overall project cost might not be fixed as in the fixed-price model, the segmented nature of the time and materials contract provides cost predictability for each phase. Clients can budget for each stage, considering the required hours and resources.

Advantages of the time and material contracts from the Client's perspective

From the client's perspective, the time and materials agreements offer several compelling benefits in software development. One key advantage is the ease of interaction. One key advantage is the ease of interaction. Unlike fixed-price contracts, which can communicate convoluted due to defined scope, T&M encourages open and streamlined communication. Clients have direct contact with a project manager who understands both the technical and business aspects, ensuring clear delegation of tasks and alignment among all stakeholders.

Another significant benefit is the high response speed. The T&M model's agility allows for quick adjustments to changes in priorities, requests, or unforeseen challenges. This responsiveness, facilitated by prompt communication with the project manager, ensures minimal disruption and delay in the project timeline.

The T&M contract also empowers clients to select team members. Instead of accepting a pre-defined team, clients can actively participate in choosing members based on their expertise and project suitability. This ensures that the right talent works on tasks that align with their strengths.

Another hallmark of the T&M model is work transparency. Through regular check-ins and feedback loops, clients can monitor project progress in near real time. This transparency fosters trust and confidence, as clients remain well-informed about the project's trajectory.

Flexibility in project scope is another advantage. T&M contracts allow for scope adjustments as the project evolves, ensuring the final product aligns with the client's current needs, a flexibility that is often cumbersome and costly in fixed-price contracts.

Lastly, the T&M contract promotes a collaborative approach. Regular interactions and feedback between the client and the software house foster a partnership that can lead to more innovative solutions and better project outcomes.

Cons of the time and material contracts from the Client's perspective

In the time and materials (T&M) contract model, clients face several disadvantages that can challenge project management and financial planning. One of the primary concerns is the lack of an accurate budget. Unlike fixed-price contracts with a predetermined budget, T&M contracts bill based on actual hours worked, making it difficult for clients to predict final costs. This uncertainty can lead to financial risks, especially if the project encounters unexpected complications or scope expansions.

Another issue is the requirement for constant interaction. While regular communication ensures project alignment and quality, it demands significant client time and effort. They need to be actively involved in discussions, reviews, and decision-making, which can be burdensome, particularly for those with multiple obligations or who prefer a hands-off approach.

There's also the risk of hiring an unscrupulous outsourcer. In a T&M model, some software houses might inflate the hours worked to increase billing, leading to exaggerated work hours, unnecessary tasks, or deliberate slowdowns. This strains the budget and erodes client and service provider trust.

Scope creep is another potential disadvantage. The flexibility of the T&M model can lead to continuous expansion of the project's scope. Projects can become larger and more complex than initially intended without a fixed scope, resulting in increased costs and extended timelines.

Pros and Cons of Time and Materials Contracts from the Contractor's Perspective


  • Focus and Quality: Allows developers to concentrate fully on the project without the constraints of fixed-price contracts, often leading to better quality outputs.

  • Transparent Payment: Links payment directly to the actual work done, motivating developers to excel in their tasks.

  • Risk Management: Breaks down the project into manageable stages, simplifying estimation and reducing uncertainties.

  • Flexibility: Offers the ability to adjust strategies as the project evolves, promoting innovation.

  • Collaboration: Encourages regular feedback from clients, aligning the end product with client expectations.

  • Resource Efficiency: Facilitates optimal allocation of resources throughout the project requirements and phases.

  • Trust Building: Transparent billing based on actual hours worked fosters long-term client relationships.


  • Unpredictable Revenue: Fluctuations in earnings due to clients adjusting hours or pausing the project complicate financial planning.

  • Administrative Burden: Requires detailed record-keeping of hours and tasks, increasing overhead.

  • Client Dependency: Project delays and increased costs can occur if clients are unresponsive or frequently change requirements.

  • Payment Risks: Potential disputes over billed hours or task necessity can lead to disagreements or non-payment.

  • Resource Challenges: Managing fluctuating work hours and scope changes can lead to resource inefficiency.

  • Scope Creep: Developers may inadvertently allow project scope to expand, straining budgets and timelines.

  • Performance Pressure: Continuous need to show progress can stress the development team, sometimes affecting quality.

In summary, time and materials contracts offer significant benefits like enhanced focus, risk management, and collaboration opportunities. However, they also present challenges such as unpredictable revenue, administrative burdens, and the pressure of continuous performance, requiring careful navigation by contractors.

When should I choose the time and material contract for my software project instead of the fixed price agreement?

When contemplating the optimal software development contracts, time and material contracts (T&M) emerge as the preferable choice in several situations. It's an ideal fit for projects with evolving or unclear requirements at the outset, providing the agility to adapt as the development progresses. This adaptability also makes time and material contract a go-to choice for ongoing or long-term projects that might need shifts in focus or direction over time. If you envision high involvement in the project, wishing for regular interactions, feedback sessions, and updates, time and material accommodate this continuous engagement. Projects on the cutting edge, exploring novel technologies or solutions, benefit from time and material's inherent flexibility, allowing for iterative adjustments as outcomes unfold. Additionally, time and material contracts often present the liberty to handpick specific team members or recalibrate team dynamics based on the project's evolving needs. A hallmark of T&M is its billing transparency, which offers clients a lucid understanding of effort versus cost, billed on actual hours worked, for those cautious about substantial upfront financial commitments or those who prefer to start with a smaller scope and scale based on visible progress, time and material contract stands out as a favorable option.

Are you looking for trusted software agency for software developement or data science project?

As Mobile Reality, we are open to different forms of cooperation, such as time and materials, fixed price, or mixed models. We provide our clients with end-to-end support in web and mobile app development projects. Don't hesitate to contact us.
CEO of Mobile Reality
Matt Sadowski
Or contact us:
North America
+1 718 618 4307
European Union
+48 607 12 61 60


Your message has been sent.

Our sales representative will contact you shortly.

The essence of the Fixed Price price model

The Fixed Price model implies an assessment of all planned works and the time required for their implementation following the client's requirement. That is, even before the start of the project, the timing and project cost are precisely determined by the development team. It is a kind of guarantee for the customer that the project will be completed by the designated date and for the agreed price. If, in the course of work, it becomes clear that more tasks need to be solved than planned, the outsourcer agrees to revise the budget with the customer, but each additional analysis takes time and has to be scheduled in accordance with the approved timeline of the project in this cooperation model.

Main Features of Fixed Price Contracts

fixed price contract for software project

Set Deadline, Price and Budget

This predetermined schedule ensures the client and the software house understand when the project or specific deliverables are due, fostering clarity in expectations and planning. Moreover, fixed-price contracts and budgetary certainty are the result of the proposed timeline. Clients know upfront how much the project will cost and the contract price, eliminating the fear of unexpected expenses. This clear financial understanding aids businesses in their financial planning and budget allocations.

Moreover, during the negotiations and clarification of the final scope and budget before starting the project, both parties, the software development company, and the client, are open to price adjustments. The vendor is more willing to offer price incentive to convince the client to choose him instead of other vendors.

Well-defined Scope

Fixed price contracts necessitate a detailed scope of work to be established at the outset. This clarity ensures that both parties understand the project's boundaries, deliverables, features, and functionalities to be developed.

Reduced Client Supervision

Given the preset scope and deliverables, clients don't need to be as intricately involved in the day-to-day development process, allowing them a more hands-off approach compared to the T&M contract.

Risk Allocation

With fixed price contracts, the risk largely shifts to the contractors, so software development companies. They commit to delivering the project within the stipulated time and budget, absorbing any additional costs arising from miscalculations or unforeseen challenges.

Payment Milestones

Typically, fixed price contracts will have predetermined payment milestones. These might be tied to completing specific phases, deliverables, or other criteria, ensuring staggered and structured payment cycles.

Penalties and Incentives

This type of contract often comes with clauses related to penalties for delays and sometimes even incentives for early completion, ensuring the software house remains motivated to stick to the schedule.

Fixed price contracts pros from the customer's point of view

In the realm of software development, fixed price contracts offer several benefits from the customer's perspective, striking a balance between predictability and efficiency. One of the key advantages is financial guarantees. Clients appreciate the financial predictability of these contracts, as they can accurately budget for the project with no fear of unexpected costs or budget overruns. This upfront clarity provides security and facilitates better financial planning.

Another significant benefit is the assurance of exact deadlines. Fixed price contracts establish a firm timeline, allowing clients to confidently anticipate project completion. This predictability is invaluable for aligning strategies, resources, and dependent tasks, ensuring smooth operations and transitions.

Efficient communication is also a hallmark of fixed price contracts. With a well-defined project scope and detailed specifications, the need for ongoing communication is reduced. This efficiency is particularly beneficial for clients who prefer a hands-off approach once the contract is established, as it frees up their resources for other strategic initiatives.

Reduced risks are another compelling advantage. The detailed technical specifications in fixed price contracts minimize ambiguity, ensuring that deliverables align closely with the client's vision and expectations. This clarity drastically reduces the potential for subpar or off-target results, ensuring clients get the value they pay for.

The transparency of deliverables in a fixed price contract is a crucial factor. It specifies what the final product will include, ensuring both parties have a mutual understanding and reducing the likelihood of discrepancies or unmet expectations.

Enhanced accountability is inherent in fixed price contracts. Software houses are obligated to meet the stipulated requirements within the set budget and timeframe, ensuring they utilize their best resources and expertise.

Evaluating vendor performance is more straightforward with fixed price contracts. Clear deliverables and timelines serve as benchmarks for evaluating the software house's efficiency and effectiveness, making the review process more straightforward.

Fixed price contracts cons from the customer's point of view

Fixed price contracts, while offering predictability and stability, present several disadvantages from a customer's point of view, particularly in the context of software development. A major drawback is the necessity for a detailed specification document. Clients need to invest considerable time and effort upfront to define every aspect of the project, from objectives and functionalities to design nuances and architectural decisions. This exhaustive process can be time-consuming and demands significant effort.

Another issue is the potential for overpayment. To cover potential uncertainties or unforeseen challenges, software houses might inflate their quotes in fixed price contracts. This built-in buffer, meant to mitigate their risks, can result in clients paying more than the actual development costs under a more flexible pricing model.

Implementing changes in a fixed price contract can be challenging. If a client needs to make alterations or additions after the project has started, it involves amending the agreement, potentially renegotiating costs and timelines, and updating documentation. This process can delay project delivery and introduce additional costs.

Communication is also a potential problem. The detailed nature of the specification document can lead to wrong interpretations or ambiguities. If the software house misunderstands certain aspects and builds features not aligned with the client's vision, correcting these can be complicated and costly.

In rapidly evolving industries or markets, adhering rigidly to a previously defined scope might make the final product obsolete or less competitive upon launch.

Lastly, strained relationships can develop if unexpected challenges arise that weren't accounted for in the original contract. Disputes over who should bear additional costs or how to proceed can strain the client-software house relationship.

Fixed price contract cons and pros from a contractor’s perspective


  • Clarity and Precision: Detailed specifications provide a clear blueprint, minimizing ambiguities and smoothing the development process.

  • Workflow Efficiency: Clear scope and deadlines streamline workflow and boost productivity by setting definite targets.

  • Financial Predictability: Fixed project costs enable accurate revenue forecasting and aid financial planning.

  • Reduced Client Interactions: Clear specifications mean fewer interruptions, leading to more focused work periods.

  • Reputation and Trust: Demonstrating reliability in meeting deliverables enhances the company’s reputation and strengthens client trust.

  • Effective Risk and Project Management: Early identification of potential challenges facilitates proactive risk management and simplifies project oversight.


  • Specification Challenges: Creating an exhaustive specification can be complex, with any missed details potentially causing discrepancies with client expectations.

  • Creativity Constraints: The fixed scope may limit innovation, with the focus shifting towards meeting deadlines over exploring better solutions.

  • Flexibility Limitations: Adapting to unexpected tasks or changes is difficult, possibly affecting project schedules and costs.

  • Financial Risks: Contractors bear the financial burden of unforeseen complexities, which can impact profitability.

  • Team Morale: The pressure to adhere to strict deadlines and specifications can strain the development team’s morale.

In essence, fixed price contracts provide clear benefits in terms of financial predictability and streamlined project management but come with their own set of challenges, such as potential specification issues, creativity constraints, and increased financial risk. Contractors must navigate these factors carefully to leverage the advantages while mitigating the downsides.

When should I choose the fixed price contract for my software project instead of the time and material model?

When considering the best approach to a software project, the fixed fee type of contract stands out as an ideal choice under specific conditions. It is particularly suited for projects that have clear, detailed, and unambiguous requirements that are set from the onset and unlikely to change during development. This model brings the benefit of financial predictability, making it an excellent choice for those operating under strict budget constraints or who desire cost stability. Furthermore, shorter projects, or relatively straightforward ones without much room for change, can benefit from a fixed price agreement. For individuals looking to reduce their day-to-day participation and decrease communication frequency, this model provides the ease of submitting detailed specifications and waiting for the completed product. Risk-averse entities will also find solace in the fixed price model, as it puts the onus of delivering within the defined budget on the software agency, ensuring that costs don't escalate unpredictably. Projects with definitive launch dates, where timely delivery is paramount, can rely on the deadlines specified in fixed price contracts. Lastly, those who may not possess in-depth technical expertise can lean on this model, relying on the software agency's expertise without constant technical discussions. In essence, for types of projects that seek clear parameters, limited flexibility, and prioritizing predictability in costs and timelines, the fixed fee contract is a commendable choice. However, to avoid potential misunderstandings and to ensure a seamless development process, it's crucial to have comprehensive documentation of the project's scope and requirements before entering such an agreement.

The essence of the MIX model

The mixed model offers a unique blend of flexibility and predictability, catering to the diverse needs of software development projects. By blending the time and materials (T&M) approach with the fixed price model, clients can adjust project specifications as needed. They can use T&M for components such as research, prototyping, or phases that are challenging to estimate and apply a fixed price to well-outlined functionalities or modules. This approach not only allows for the dynamic evolution of the project but also provides the stability of cost and timeline predictability. Such a structure ensures that clients can benefit from the adaptability required during the initial stages of development while locking in costs for more predictable segments of the project.

Additionally, the mixed model effectively distributes risks between the software house and the client, creating a more balanced and equitable relationship. Through the T&M component, contractors are guaranteed fair payment for tasks requiring exploration or that have a higher level of uncertainty. Meanwhile, the fixed price part of the contract locks in a specific cost for well-defined sections of the project. This arrangement fosters enhanced collaboration, as the T&M portion encourages ongoing communication and feedback, and the fixed price section establishes a mutual understanding of specific deliverables. Moreover, the model supports scalability; as the project unfolds and its complexities become clearer, additional phases can transition from T&M to fixed price, facilitating more precise budgeting and scheduling as the project advances. Mixed Model should be considered for:

  • Large Projects: For extensive projects with both well-defined phases and areas of uncertainty, a mixed model can be beneficial.

  • Startups and Innovations: When developing a new product or solution where the initial stages involve research, experimentation, or iterative development, the T&M component is handy. As features get defined, they can transition to a fixed price model.

  • Ongoing Partnerships: If there's an established relationship between a client and a software house, a mixed model can foster collaboration, with the software house sometimes even suggesting which components should be T&M vs. fixed price.

In conclusion, while the mixed model offers a balanced approach, its success largely depends on clear communication, well-defined contracts, and trust between both parties. It's a model that requires maturity and understanding from both the client and the software development company. When executed well, it can offer the best of both worlds, combining the adaptability of T&M with the predictability of a fixed price contract.

Are you looking for trusted software agency for software developement or data science project?

As Mobile Reality, we are open to different forms of cooperation, such as time and materials, fixed price, or mixed models. We provide our clients with end-to-end support in web and mobile app development projects. Don't hesitate to contact us.
CEO of Mobile Reality
Matt Sadowski
Or contact us:
North America
+1 718 618 4307
European Union
+48 607 12 61 60


Your message has been sent.

Our sales representative will contact you shortly.


In the intricate dance of software development and cooperation with a software house, the billing model and contract type choice aren't just about costs. It's about aligning expectations, managing risks, and ensuring a successful outcome. With its predictability and well-defined scope, the Fixed Price model offers clarity and security, making it particularly suitable for projects with precise requirements and boundaries. Conversely, the T&M model offers flexibility, adapting to changing needs and fostering collaboration, particularly for projects with uncertainties or focused on innovation.

Ultimately, choosing the right billing model depends on the project's nature, the client-software house relationship, and the desire for risk and flexibility. It's vital to carefully assess the pros and cons to choose a model that promotes teamwork, suits the project's needs, and leads to success. As the world of software development continues to evolve, so too will these models, but the core principles of clarity, collaboration, and value will remain paramount.

Exploring the Business Facets of Software Development

The business strategy behind software development is as crucial as the technology itself. At Mobile Reality, we provide a deep dive into the various business models, methodologies, and strategies that drive profitable and efficient software creation. Our comprehensive articles are designed to guide you through the complexities of the custom software development business:

These resources are crafted for those looking to refine their approach to building and managing software projects. Whether you’re contemplating the most effective development methodology, weighing the pros and cons of outsourcing, or deciding on the right pricing model, our insights can lead to informed decisions. Contact our team for a personalized consultation on software development business strategies. We’re here to help you navigate the path to success in the digital product landscape.

Did you like the article?Find out how we can help you.

Matt Sadowski

CEO of Mobile Reality

CEO of Mobile Reality

Related articles

Unlock the secrets of Software SLA Agreements in the tech world. Learn how to navigate and negotiate effectively. Click here for expert tips and insights!


Understanding Software SLA Agreements

Unlock the secrets of Software SLA Agreements in the tech world. Learn how to navigate and negotiate effectively. Click here for expert tips and insights!

Read full article

Discover how to unlock the full potential of NFT marketplace development in 2024. Maximize your profits with cutting-edge strategies. Learn more now!


Maximize Your NFT Marketplace Development in 2024

Discover how to unlock the full potential of NFT marketplace development in 2024. Maximize your profits with cutting-edge strategies. Learn more now!

Read full article

Explore key insights from CREtech London on real estate innovation in proptech and sustainable practices. #CREtechLondon #Proptech #RealEstate


CREtech London 2024 : Key Highlights and Insights

Explore key insights from CREtech London on real estate innovation in proptech and sustainable practices. #CREtechLondon #Proptech #RealEstate

Read full article