How to Write a Software Project Brief That Gets You Accurate Quotes
We review about 15-20 project briefs every month at Quantum Horizon. Roughly 3 out of those 20 are good enough to produce an accurate quote without a follow-up call. The rest are either a wall of text that buries the important details, or a paragraph so vague that we would need to triple the estimate just to cover the unknowns.
The fix is not complicated. A strong software project brief follows a predictable structure, takes 2-3 hours to write, and saves you weeks of wasted time during the vendor evaluation phase. Here is the exact format that produces the best results.
What a Brief Is and Is Not
A project brief is not a requirements document. It is not a technical specification. It is a concise description of what you need, why you need it, and the constraints the solution must fit within. Think of it as a job posting for your project - enough detail to attract the right candidates, not so much that nobody reads it.
A brief should be 2-5 pages. If yours is longer than 5 pages, you are probably including implementation details that belong in a later phase. If it is shorter than 2, you are probably leaving out information the agency needs to quote accurately.
The Seven Sections Every Brief Needs
1. The Problem Statement
Start with the business problem, not the solution. This is the most important section and the one most briefs get wrong. Do not say "we need a mobile app." Say "our field technicians spend 3 hours per day on paperwork that could be automated, and we are losing $420,000 annually in productivity."
A brief that starts with the problem gives the development team permission to propose the best solution - which might be different from what you originally imagined, and often better.
2. Target Users
List every user type who will interact with the system. For each one, include their role, approximate count, technical comfort level, and primary goal. A CRM used by 5 sales reps has very different requirements than one used by 500. An app for warehouse workers with gloves needs bigger buttons than one for office staff.
3. Core Features - Prioritized
List your features in three buckets: must-have for launch, important but can wait for V2, and nice-to-have. Be specific. Instead of "reporting," write "monthly PDF report showing revenue by product category, emailed to admin users on the 1st of each month."
Keep the must-have list to 5-8 items. If you have 20 must-haves, you have not prioritized - you have listed everything. An agency cannot give you an accurate quote on a wish list. They can give you an accurate quote on a focused scope.
4. Constraints and Requirements
- Budget range - even a broad bracket like $50K-$150K helps enormously
- Hard deadlines - regulatory, seasonal, or market-driven dates that cannot move
- Compliance - GDPR, HIPAA, SOC 2, PCI-DSS, or industry-specific standards
- Hosting preferences - cloud provider, on-premise requirements, data residency
- Existing systems - what the new software must integrate with
5. Success Metrics
Define what success looks like in numbers. "Reduce order processing time from 45 minutes to under 10 minutes." "Achieve 80% user adoption within 90 days of launch." "Handle 10,000 concurrent users without performance degradation." These metrics help the agency make technical decisions that align with your actual goals.
6. Existing Work
Share what already exists. Wireframes, mockups, a prototype, an old system being replaced, API documentation, brand guidelines - anything relevant. Also share what has been tried before and why it did not work. This prevents agencies from proposing solutions you have already rejected.
7. Decision Process and Timeline
Tell agencies how you plan to evaluate proposals and when you need to make a decision. Are you comparing three vendors? Is there a board approval step? When does the project need to start? This information helps agencies prioritize your proposal and set expectations on both sides.
Before and After: Vague vs. Clear Brief
Here is what the difference looks like in practice.
The Vague Version
We need a web app for managing our inventory. It should be modern-looking and easy to use. We want it done quickly and within a reasonable budget. Please send us a proposal.
This brief gives the agency almost nothing to work with. How many products? How many warehouses? What does "modern" mean? What is "quickly" - 4 weeks or 6 months? What is "reasonable" - $20K or $200K? Any quote based on this will either be wildly inflated to cover unknowns or artificially low to win the deal.
The Clear Version
We run 3 warehouses with a combined 12,000 SKUs. Currently tracking inventory in spreadsheets, which causes 8-12% stock discrepancy per quarter. We need a web application where warehouse staff (15 users) can scan items in/out using barcode scanners, and managers (4 users) can view real-time stock levels and generate reorder reports. Must integrate with our Xero accounting system. Budget is $60K-$100K. Need MVP live by March 2025. Must-haves: barcode scanning, stock levels dashboard, low-stock alerts, Xero sync. V2: predictive reorder suggestions, multi-warehouse transfer workflows.
Same project. But now any competent agency can give you a quote within $10K-$15K of the actual cost. The clear version took maybe 30 minutes longer to write and will save you weeks of clarification calls.
What to Leave Out of Your Brief
Knowing what to exclude is just as important as knowing what to include. These details belong in the discovery phase, not the brief.
- Specific technology choices - unless you have a hard requirement, let the agency recommend the stack
- Database schema or architecture diagrams - this is their job
- Pixel-perfect designs - rough wireframes are helpful, but final designs come after the brief is accepted
- Implementation approach - describe the what, not the how
- Every edge case you can think of - save these for discovery workshops
The Budget Range Objection
Clients push back on including budget range more than any other section. The concern is always the same: if I tell them my budget is $100K, they will quote $100K regardless of the actual cost.
Here is the reality: without a budget range, agencies either quote conservatively high (to cover risk) or strategically low (to win the deal and negotiate changes later). Neither outcome helps you. With a range, a trustworthy agency will tell you what is achievable at the low end and what the full scope costs. If $60K buys you 80% of what you need and the last 20% costs another $40K, that is useful information for making a decision.
If you are genuinely unsure about budget, say so - but add context. "We are early stage and capital-constrained" is more useful than silence. "We have board approval for up to $200K for this initiative" is even better.
Send It to Three Agencies, Not Ten
A common mistake is blasting your brief to a dozen agencies and comparing proposals. The problem: evaluating ten proposals takes significant time, the proposals will vary so wildly in format and assumptions that comparison is nearly impossible, and agencies who suspect they are one of ten will invest less effort in their response.
Shortlist three agencies based on portfolio, reviews, and an initial call. Send the brief to all three. Give them the same deadline (10-14 business days is reasonable for a Tier 2 project). Compare the proposals on structure, specificity, and how well they addressed your stated problem - not just on price.
Your Next Step
Take 2-3 hours this week and write your brief using the seven sections above. If you can answer each section in 3-5 sentences, you will have a document that any serious development partner can turn into an accurate, detailed proposal. The time you invest now pays back tenfold in fewer surprises, tighter estimates, and a smoother project from start to finish.
