How to Write a Software Requirements Document (Even If You Are Not Technical)
A clear requirements document gets you more accurate quotes and fewer surprises. Here is what to include and a simple template you can fill in.
DevGlim Team
October 23, 2026
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If you send three development companies a two-line description, you will get three very different quotes, because each one is guessing. A software requirements document removes most of that guessing. You do not need technical knowledge to write a useful one. You need to describe your business problem, the people involved and what "done" looks like. This guide shows you how.
What a requirements document is for
- It lets developers estimate cost and time accurately.
- It makes quotes from different vendors comparable.
- It gives everyone a shared reference when questions come up during the build.
- It defines when the work is finished, through acceptance criteria.
It does not need to be long. A clear ten-page document is more useful than a vague fifty-page one.
The sections to include
1. Background and goal
Explain the problem in business terms. "Our team spends about two days a month re-typing orders from email into our accounting system, and mistakes delay invoices" is far more useful than "we need an order portal". State the goal you will measure, such as fewer errors or faster invoicing.
2. Users and roles
List who will use the system and what each type of user should be able to do: customers, staff, managers, administrators. Note roughly how many of each.
3. Key workflows
Describe the main tasks step by step, from the user's point of view. For example: "A customer logs in, uploads a purchase order, reviews the extracted lines, confirms, and receives an email confirmation." Workflows reveal requirements that feature lists miss.
4. Features, prioritised
Group features into must have, should have and nice to have. This is the single most useful thing you can do to control cost, because it lets a developer propose a smaller first release.
5. Data
What information does the system store? Customers, orders, products, documents? Where does that data live today, and does existing data need to be migrated?
6. Integrations
List every system the new software must connect to, such as accounting, CRM, payment, email or shipping, and what should flow between them. Include links to their API documentation if you have them.
7. Non-functional requirements
These describe how the system should behave rather than what it does: expected number of users, devices and browsers, accessibility, data protection or industry rules, availability, and where data must be hosted.
8. Acceptance criteria
For each important feature, write how you will know it works. "When a customer uploads a valid PDF purchase order, the line items appear for review within one minute" can be tested; "upload should be easy" cannot.
9. Constraints
Budget range, target launch date, preferred technologies or hosting, and anything that must not change.
10. Open questions
List what you do not know yet. Good developers will help you answer these during discovery, and it shows them where the estimate is uncertain.
A simple template
| Section | What to write |
|---|---|
| Goal | The problem today, the result you want, how you will measure it |
| Users | Each role, what they do, approximate numbers |
| Workflows | 3 to 6 main tasks, step by step |
| Features | Must / should / nice to have |
| Data | What is stored, current location, migration needs |
| Integrations | Systems, direction of data, API links |
| Non-functional | Scale, devices, security, compliance, hosting |
| Acceptance criteria | Testable statements per key feature |
| Constraints | Budget range, dates, technology preferences |
| Open questions | What you are unsure about |
Common mistakes
- Describing solutions instead of problems. Explain what you need to achieve; let the developer propose how.
- Treating everything as a must have. That removes your best lever on cost.
- Leaving out edge cases. What happens with refunds, cancellations, missing data or duplicate records?
- Forgetting the admin side. Someone has to manage users, settings and content.
- Writing it alone. Ask the people who will use the system to review the workflows.
Next step
Not sure whether you need custom software at all? Try the custom vs off-the-shelf assessment. Our custom software development guide explains the full process. If you have a draft, DevGlim's team is happy to review it and point out gaps before you request quotes.
