Fixed price or time and materials: which fits your project?
If you can write down the pages, languages and features you need before work starts, a fixed price usually protects you better: the supplier commits to a number for a defined scope and carries the risk if the work takes longer.
If the scope will genuinely change as you go, because you are testing ideas or the requirements depend on things nobody knows yet, time and materials is more honest, but you must watch the hours.
Most business websites in Bangkok, a hotel or resort website, a clinic website, a shop, fall into the first group. Their pages and features can be listed in an afternoon. Open-ended work is more common in custom software than in websites.
The terms
- Fixed price: one agreed price for an agreed scope, usually paid in stages.
- Hourly: you pay for the hours worked, at an agreed rate.
- Time and materials (T&M): hours plus any costs such as paid plugins, themes or stock photos, billed as they occur.
- Capped T&M: time and materials with an agreed maximum; the supplier stops and asks before going over.
Whichever model you choose, the underlying price still depends on scope. For typical ranges, see our guide on how much to make a website in Thailand.
Fixed price and time and materials compared
The table sets the two models side by side on the points that matter to a buyer. Neither is better in general; each fits a different kind of project.
| Point | Fixed price | Time and materials |
|---|---|---|
| Best for | A scope you can define before work starts | A scope that will evolve during the work |
| Who carries overruns | The supplier, within the agreed scope | You, unless there is a cap |
| Cost predictability | High: one number for the defined work | Low to medium: depends on hours used |
| Changes during the project | Priced as change requests | Absorbed into billed hours |
| Effort on your side | Define scope clearly upfront | Track hours and priorities throughout |
| Risk of padding | Supplier may add a buffer to the price | Work may expand to fill available hours |
| Flexibility | Lower: changes need agreement | Higher: direction can shift week to week |
Who carries the risk
Every project has uncertainty: a layout takes longer than expected, a payment plugin misbehaves, content arrives late. The pricing model decides who pays for that.
Under a fixed price
The supplier absorbs the extra hours on work inside the scope. That is why a fixed quote often includes a buffer, and why a good supplier insists on a detailed scope: they are pricing the risk. Your risk shifts to the edges. Anything not written into the scope is extra, so a vague scope simply moves the argument to later.
Under time and materials
You pay for every hour, including the ones spent on problems. In return, you are not paying a buffer for risks that never happen. This rewards buyers who are organised, decide quickly and supply content on time, and punishes slow feedback, because waiting and rework both cost hours.
What it means for total cost
On a well-defined website, a fixed price is usually more predictable and often similar in total. On an uncertain project, time and materials can be cheaper if things go well and much more expensive if they do not. Ask yourself which outcome you can afford, not only which is likely.
How changes are handled
Changes are where the two models feel most different day to day.
On a fixed-price project, a change request is anything outside the agreed scope: an extra page, a new booking rule, a third language. The supplier should describe the change, price it and wait for your written approval before doing it. Revisions inside the scope, such as adjusting colours or wording within the agreed revision rounds, should not trigger a new charge. The quality of this process depends on how clearly the original scope was written, which is why a website design quote example is worth studying before you sign anything.
On time and materials, changes need no paperwork: the hours simply go on the bill. That speed is convenient, but it is also how budgets drift. A request to "just move the form" can take ten minutes or half a day depending on how the site was built.
A practical rule for either model: keep a running list of changes with a date, who asked and what it cost. It keeps both sides honest and makes the final invoice easy to check.
Hybrid models
You do not have to choose one model for the whole job. Two hybrids work well for websites.
Fixed discovery, then fixed build
A short, separately priced planning stage produces the page list, features and wireframes. With that in hand, the build can be quoted at a fixed price with far less buffer. This suits larger sites where you are not yet sure what you need, and it gives you a document you could take to another supplier if you wished.
Capped hours
Time and materials with a ceiling. The supplier bills actual hours but must stop and ask before exceeding the cap. This suits ongoing improvements after launch, where tasks are small and varied.
Pricing models are only one part of how suppliers set their fees. For a wider look at day rates, value pricing and packages, read our guide on how web designers decide how much to charge, written from the supplier side. And if you are weighing a do-it-yourself builder against hiring anyone at all, compare builder costs vs an agency first.
Three example projects
These are hypothetical examples to show how the choice plays out, not real client projects.
A five-page company site
A new accounting firm needs home, services, about, pricing and contact in English. The scope fits on one page of paper. Fixed price is the clear choice: there is little uncertainty for a supplier to charge for, and you know the total before you start.
A bilingual 15-page site
A clinic wants Thai and English versions, treatment pages, a booking enquiry form and a blog. The scope is still definable, but content is the risk: who writes the Thai, and when will doctor profiles arrive? Fixed price still works, provided the quote states who supplies content and what happens if it is late. Understanding website design vs website development helps here, because design revisions and build changes are often priced differently.
An e-commerce store
A fashion retailer wants a store with PromptPay, cards, cash on delivery and Thai courier shipping. The build can be fixed, but the product import is the variable: 80 products with clean data is quick; 2,000 with missing photos is not. A fixed build plus a clearly stated import allowance, or capped hours for data clean-up, keeps both sides safe. Remember that platform fees sit outside either model; our note on Shopify pricing in Thailand explains the running costs.
How we price
We work on a fixed-scope basis. Our packages give indicative starting prices: Starter from THB 10,000 for up to five pages, Business from THB 30,000 for up to 15 pages in English and Thai with two revision rounds, and E-commerce from THB 50,000 on Shopify or WooCommerce. These are one-time "from" prices, and you can compare what each includes on our package prices page.
Every project then gets a written quote that sets out the scope, what is excluded and the final price. Payment terms are set out in that quote. If you ask for something outside the agreed scope during the project, we describe and price it before doing it, so the total only changes when you agree to a change.
A typical project takes about 15 days; large product catalogues take longer, and the quote says so. Send us your page list or a rough brief and we will reply with a website development quote for that scope.
Builds and ranks the websites: the systems behind the 17 client sites whose Search Console numbers we publish. This guide was written by the Website Development Bangkok team. More about us