How to Write an RFP for Software Development
Practice4 minInnovialabs editorial team
In short
A good RFP describes the problem, users, features, constraints and the expected response format, and proposals are scored against weighted criteria set in advance — not on price alone.
What an RFP is and when you need one
An RFP (Request for Proposal) is a document you send to several vendors to get comparable proposals for a project. You need it when you are choosing between several companies and want to compare answers on the same parameters.
The main purpose of an RFP is to give vendors enough information for an accurate estimate. The fewer unknowns, the less "risk buffer" goes into the price and the closer the answers are to one another.
RFP structure
1. About the company and the project
Briefly: what the company does, why the project is needed and which business problem it solves. State how you will measure success.
2. Users and scenarios
Who will use the system and what exactly they will do. Scenarios like "a manager receives a request, assigns an executor, the customer sees the status" give a vendor more than an abstract feature list.
3. Functional requirements
List the features and mark the priority of each: required for launch, desirable, can come later. This lets vendors propose a phased plan.
4. Non-functional requirements
- expected load and number of users;
- security and data storage requirements;
- interface languages;
- platforms: web, iOS, Android;
- accessibility and performance requirements.
5. Integrations and current infrastructure
Which systems already exist: CRM, accounting software, payment services, inventory. Do they have APIs, and who maintains them?
6. Constraints
Desired timeline, budget range (at least a bracket), and technology preferences if they are justified — for example, your in-house team will maintain the product on a specific stack.
7. What you expect in the response
Set one response format, otherwise comparison becomes hard:
- understanding of the problem in their own words;
- proposed solution and stack;
- plan by phases and timeline;
- cost estimate broken down by phase;
- team composition;
- relevant experience;
- payment model and support terms;
- assumptions and risks.
8. Selection process and timeline
Deadline for questions, response deadline, decision date and contact person.
How to make estimates more accurate
- Attach materials: mockups, examples, process diagrams.
- Allow questions and share the answers with all participants — it levels the playing field.
- Ask vendors to list assumptions. Price differences are often explained by companies understanding the scope differently.
- Do not demand a fixed price if requirements are still rough. Ask for a range plus the cost of a discovery phase instead.
How to score responses
Build a table of weighted criteria before you receive the answers. An example set:
| Criterion | What to check |
|---|---|
| Understanding | Did the vendor restate your problem, not a template? |
| Solution quality | Is the stack justified, are integrations covered? |
| Experience | Are there similar projects you can actually see? |
| Team | Who specifically will work on the project? |
| Timeline and plan | Realistic, with intermediate deliverables? |
| Cost | Transparent breakdown, what is included? |
| Process | Reporting, communication, handling change |
Each reviewer scores independently, then the results are combined. You choose the weights based on what is most critical for your project.
Common mistakes
- A document that is too generic — the responses will not be comparable.
- A document that is too detailed, with a ready-made architecture — you lose the vendors' expertise.
- Choosing on price alone. The cheapest proposal often simply includes less work.
- Sending it to dozens of companies. Comparing many responses properly is hard; it is wiser to build a shortlist first.