Fixed price vs time-and-materials — which is safer?
Fixed price feels safer and often isn't. To cover the risk of a fixed bid, agencies pad it — commonly 15–30% — and then have every incentive to cut corners to protect the margin. Time-and-materials needs trust but keeps the work honest. The safest setups scope tightly first, then phase the build so cost is controlled without hiding it.
What each really means.
- Fixed price — certainty on paper, a 15–30% risk buffer baked in, and pressure to cut corners.
- Time-and-materials — you pay for what's built; needs trust and good scoping to feel safe.
- The hidden cost of fixed — change requests for anything not in the original spec.
- The risk of T&M — an open meter with no discipline can drift.
Scope first, then phase.
The honest answer is rarely a pure model. Scope the work properly up front so 'done' is defined, then deliver in priced phases with working software at each step. You get cost control and visibility without paying a fat risk buffer or signing a blank cheque — and you can stop between phases if you choose.
Common questions.
Is fixed price or time-and-materials safer for the client?
Fixed price feels safer but bakes in a 15–30% risk buffer and incentivises corner-cutting. Time-and-materials is honest but needs trust. The safest setups scope tightly first, then phase the build with priced stages.
Why is fixed-price software development risky?
Because to cover their risk, agencies pad the price and then protect that margin — often by cutting corners or charging change requests for anything outside the original spec. The certainty is partly an illusion.
What's the problem with time-and-materials?
Without good scoping and discipline it can drift — an open meter with no defined 'done'. It works well when scope is clear and the work is phased, less well when neither is.
What pricing model do you recommend?
Scope first so 'done' is defined, then deliver in priced phases with working software at each step. It gives cost control and visibility without a hidden risk buffer or a blank cheque.
Can I get a fixed price after scoping?
Often yes — once scope is defined through discovery, a phase can be priced firmly. The mistake is fixing a price before anyone knows what's actually being built.
How do I avoid change-request surprises?
Define scope properly up front and use a clear change process, so changes are a deliberate decision with a known cost — not a surprise line on the invoice.
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Related questions
Price it honestly.
Book a call and we'll explain exactly how we scope, phase and price — no hidden buffer, no blank cheque.