When you hire a software company, the price is only half the decision. How you pay shapes risk, flexibility and quality. The two most common models are fixed price and time and materials (T&M). Neither is “better” — they suit different situations.
What each model means
| Fixed price | Time and materials | |
|---|---|---|
| How you pay | One agreed total (often in milestones) | For actual hours or monthly team cost |
| Scope | Defined upfront | Can evolve |
| Budget certainty | High | Medium (needs a cap and tracking) |
| Flexibility | Low — changes need approval and cost | High |
| Best for | Well-defined projects | New products and uncertain requirements |
Fixed price: certainty, with conditions
Advantages
- You know the total cost and timeline in advance.
- Easy to compare quotes and get approval.
- The vendor carries more delivery risk.
Watch-outs
- The scope must be written in detail; vague scope leads to disputes.
- Changes are paid as extras, so flexibility is limited.
- Vendors may add a risk buffer or cut corners if the estimate was too low.
Great for: a brochure website, a standard e-commerce store, a clearly specified internal tool. See typical examples in our website cost guide.
Time and materials: flexibility, with discipline
Advantages
- You can change direction as you learn from users.
- You pay for the work actually done.
- Ideal for products where requirements are discovered along the way.
Watch-outs
- Without controls, costs can drift.
- You need regular reviews and clear priorities.
- You must trust the team’s estimates and reporting.
Great for: a new SaaS product, an AI project with uncertain data, an app that will evolve over many releases. See our SaaS MVP roadmap.
The best of both: phased fixed price
Many successful projects use a hybrid:
- Discovery (fixed, short): requirements, designs and estimate.
- MVP (fixed price): a clearly defined first version.
- Improvements (T&M or monthly retainer): ongoing features driven by feedback.
You keep control, limit risk and still adapt.
How to choose
Ask yourself:
- Can I describe the complete scope in writing today? If yes → fixed price. If no → T&M or phased.
- Will I learn things that change the plan? If yes → T&M or phased.
- Do I need a strict budget cap for approval? → fixed price per phase.
- Do I have time to manage priorities weekly? If no → fixed price may be easier.
Contract tips whichever model you choose
- Write deliverables and acceptance criteria clearly.
- Pay against milestones, not entirely upfront.
- Agree how change requests are priced.
- Confirm ownership of code and designs.
- Include a support period after launch.
- Ask for regular demos and reports.
Our guide on how to choose a software development company has a full checklist, and our app cost guide explains what moves price.
Talk to us about your project
We offer clear written quotes, phased pricing and regular demos. Get a free quote or explore our custom software service.
