Hiring a bid writing service is an investment. Like any investment, it needs to be measured. Too many businesses engage external bid support and judge the outcome solely on whether they won or lost, without looking at the underlying indicators that reveal whether the service is actually performing.
This guide sets out a structured framework for evaluating bid writing effectiveness across four areas: ROI metrics, evaluator and client feedback, compliance and quality, and project management. It also covers win rate benchmarks, what good reporting looks like, and the red flags that should prompt you to reconsider your current provider.
The Three Core ROI Metrics
To evaluate the return on investment from a bid writing service, track these three metrics consistently across every submission.
1. Win Rate
Win rate is the most straightforward measure: the number of bids won divided by the total number of bids submitted over a defined period. Track this before and after engaging the service so you have a meaningful baseline to compare against.
Win rates vary significantly by sector and contract type, so a single number in isolation tells you little. What matters is the trajectory. A consistent upward trend over six to twelve months is a reliable indicator that the service is improving your positioning and the quality of your submissions.
| A professional bid writing service should be able to show you their average win rate across clients. At DellaPip, we achieve an 85% success rate on bids submitted, against a sector average that typically sits between 25% and 40% for competitive public sector procurement. |
2. Score Improvement
Win rate alone does not tell you why you are winning or losing. Score improvement does. After each submission, request a debrief from the buyer. Compare your evaluator scores on bids written by the service against your historical scores on self-written bids.
Look specifically at question-level scores, not just your overall total. If you are losing marks consistently on social value, methodology, or mobilisation questions, that is a signal about either the quality of the writing or a gap in the evidence and case studies your service is drawing on.
An improvement of ten or more points on a 100-point scale, or a meaningful shift in your ranking among bidders, is a strong indicator of genuine performance improvement.
3. Cost Per Bid vs. Contract Value
Calculate how much you spend on the service relative to the total value of contracts secured. As a general benchmark, a bid writing fee that represents two to five percent of the contract value it helped secure is a reasonable return. For high-value contracts, the ratio will often be significantly more favourable.
Also account for the opportunity cost of your own team’s time. If directors or senior managers are no longer spending days on bid responses, that recovered time has real commercial value that should be factored into the calculation.
Learn more on: Is Hiring a Bid Writing Agency Worth It? Understanding the ROI
The Full Evaluation Framework
| Metric | How to measure it | What a good result looks like |
| Win rate | Bids won divided by total bids submitted | Consistent upward trend over 6 to 12 months |
| Score improvement | Compare evaluator scores before and after engaging the service | Improvement of 10 points or more on a 100-point scale |
| Cost per bid vs. contract value | Total service cost divided by total contract value secured | Service fee under 2 to 5% of contract value on average |
| Compliance rate | Percentage of submissions with zero non-compliance flags | 100%; any disqualification is a critical failure |
| Feedback quality | Debrief scores and evaluator comments on structure, evidence, and tailoring | Positive commentary on clarity, specificity, and responsiveness to criteria |
How to Use Evaluator and Client Feedback
Always request a debrief
After every bid outcome, win or loss, ask the buying organisation for a debrief. Most public sector buyers are required to provide one on request. This is not optional if you are serious about improving. The debrief gives you qualitative and quantitative feedback that no internal review can replicate.
A good bid writing service will either conduct this debrief on your behalf, attend it with you, or help you prepare the right questions in advance.
Analyse scorecards at question level
Do not stop at your overall percentage score. Break it down by question or lot. If you scored 7 out of 10 on methodology but 3 out of 10 on social value, those are very different problems requiring different responses. Compare your scores against the winning bidder where that information is available.
This analysis will tell you whether underperformance is due to a writing quality issue, a gap in the evidence you are providing, or a strategic misalignment between your answer and what the buyer was actually looking for.
Perform a win/loss analysis after every bid
A structured win/loss analysis goes beyond the debrief. It asks whether the bid writer clearly communicated your corporate capability, whether the narrative was specific to the buyer or generic and templated, and whether the evidence used was drawn from comparable contracts or lifted from unrelated case studies.
Assessing Compliance and Quality
Compliance is non-negotiable
Disqualification through non-compliance is the most avoidable failure in bid writing. A professional service should ensure that every mandatory question is answered, every word limit is respected, and every formatting requirement and document checklist item is met before submission.
If a bid you have paid for is rejected for non-compliance reasons, that is a fundamental failure. It should not happen. If it does, it is a serious red flag about the service’s internal quality assurance process.
Clarity, specificity, and tailoring
Beyond compliance, evaluate quality along three dimensions. First, clarity: does the response answer the question directly in the opening sentence, or does it take a paragraph to get to the point? Second, specificity: does it use quantifiable evidence drawn from comparable contracts, or does it rely on vague claims about your organisation’s capabilities? Third, tailoring: does it address the buyer’s specific priorities and pain points, or does it read like a generic template with your company name inserted?
Generic, copy-pasted responses are the most common reason good companies score poorly on bids they should be competitive for. A quality bid writing service will produce responses that feel specific to that buyer, that contract, and that moment.
Auditing the Project Management Process
Subject matter expert engagement
An effective bid writer does not work in a vacuum. They need to extract technical knowledge, operational evidence, and commercial context from your internal team. Evaluate how well your service manages this process. Are their information-gathering sessions structured and time-efficient? Do they ask the right questions? Are they causing unnecessary disruption to your operations, or have they developed a lean briefing process that respects your team’s time?
The quality of the final submission often reflects the quality of the briefing process. A service that struggles to extract information is likely producing responses that underrepresent what your business actually does.
Adherence to deadlines and review cycles
Assess whether drafts are consistently delivered with enough time for your internal review and sign-off before submission. A good service builds a timeline at the start of every bid that includes milestones for first draft, client review, revisions, and final submission. Compressed timelines at the end of a bid are usually a sign of poor planning at the front end.
If you are regularly receiving drafts with less than 48 hours to review and approve before a submission deadline, that is a structural problem with how the service manages bid delivery.
What Good Reporting Looks Like
A professional bid writing service should provide transparent, consistent reporting on every submission. Here is what to ask for and what a high-quality response looks like.
| What to ask for | What good looks like |
| Win/loss summary per bid | A clear record of outcome, score received, and score of the winning bidder where available |
| Evaluator feedback notes | Annotated buyer debrief notes with commentary on what to improve next time |
| Compliance checklist | A completed checklist for every submission confirming mandatory requirements were met |
| Time to draft | Drafts delivered with enough time for your internal review, sign-off, and revision cycle |
| Question-level score analysis | Breakdown of scores by question or lot so you can identify where you are losing marks |
| Improvement recommendations | Written recommendations after every loss, not just a summary of what happened |
| At DellaPip, every client receives a post-bid summary after each submission, including outcome, scores where available, debrief notes, and specific recommendations for the next bid. Transparency is part of the service, not an optional add-on. |
Red Flags to Avoid
Not all bid writing services deliver equal value. These are the warning signs that should prompt you to ask harder questions, or reconsider your provider entirely.
| Red flag | Why it matters |
| Guaranteed win rates | No one can guarantee a win. Promises of 90%+ success are a sales tactic, not a performance benchmark. |
| No debrief process | If they do not help you request and review buyer feedback after each bid, they are not helping you improve. |
| Generic templates with light edits | Copy-paste responses that are not tailored to the buyer’s specific criteria will score poorly every time. |
| Unclear pricing or hidden fees | A reputable service will give you a clear scope and cost before work begins. |
| No named writer or single point of contact | You need to know who is writing your bid and be able to brief them directly. |
| Resistance to sharing previous scores or case studies | If they cannot evidence their track record, treat that as a warning sign. |
| Missing mandatory requirements or formatting errors | Disqualification through non-compliance is a fundamental failure that should never happen with a professional service. |
| If a service guarantees you will win, walk away. Procurement outcomes depend on competition, buyer criteria, and your price point, none of which any bid writer controls. What a good service guarantees is quality, compliance, and a structured process. |
Win Rate Benchmarks by Context
Win rates vary significantly depending on sector, contract type, and the competitiveness of the opportunity. These benchmarks give you a useful reference point when evaluating performance.
- Open competition, public sector: 20 to 35% average win rate for competitive bidders
- Framework call-offs: 40 to 60% where you are already an appointed supplier
- Restricted or pre-qualified shortlists: 25 to 50% depending on the number of shortlisted suppliers
- DellaPip client average: 85% across all bids submitted
If your win rate is consistently below 20% across a range of bids, the issue is unlikely to be price alone. It is worth commissioning a bid audit to identify where you are losing marks before spending further on submissions that are not competitive.
The Qualities That Define a Strong Bid Writing Service
Beyond the metrics, the right bid writing partner will demonstrate these qualities consistently.
- Proven track record: High win rates evidenced by case studies and client references, not just claims on a website.
- Sector expertise: Understanding of your industry’s language, regulatory context, and procurement priorities.
- Structured research process: They analyse the buyer’s priorities, the competitive landscape, and your own differentiators before writing a word.
- Clear, persuasive writing: Concise responses that answer the question directly, use evidence effectively, and link your capabilities to the buyer’s outcomes.
- Genuine collaboration: They work with your team, not around them, and take feedback constructively.
- Compliance rigour: A documented checklist process that eliminates the risk of disqualification.
- Commitment to improvement: Post-bid analysis, debrief support, and written recommendations after every outcome.
How DellaPip Measures Up
At DellaPip, we apply this framework to every engagement. Our clients receive transparent reporting, structured bids, and a dedicated point of contact who knows their business. We track win rates, score trends, and evaluator feedback across every submission, and we share that data with clients so they can see exactly where improvement is happening.
With over £2.5 billion secured in contract wins and an 85% bid success rate, we have a track record that we are happy to evidence. If you are currently working with a service that cannot show you comparable data, that gap is worth exploring.
| Ready to evaluate whether your current bid support is performing? Book a free 15-minute chat with the DellaPip team and we will walk you through how we measure performance and what a stronger bid function could look like for your business |
Frequently Asked Questions
What is a good win rate for a bid writing service?
In open public sector competition, a win rate of 30 to 40% is considered strong for competitive bidders. Rates consistently above 50% across a broad range of opportunities are exceptional. If a service claims significantly higher rates across all bid types, ask to see the evidence behind those numbers.
How do I know if a bid writing service is actually improving my submissions?
Request evaluator debriefs after every bid and track your question-level scores over time. If scores are improving on the specific questions the service is writing, that is strong evidence of quality. If scores are static or declining despite using the service, that warrants a direct conversation about what is going wrong.
What should a bid writing service provide after a failed bid?
At a minimum: a post-bid summary, the evaluator debrief notes (or support in obtaining them), a question-level score analysis, and written recommendations for improving the next submission. If your current service is not providing this, ask for it. If they are unwilling or unable to, treat that as a red flag.
Can I measure the ROI of a bid writing service?
Yes. Calculate the total cost of the service across a defined period and compare it against the total contract value secured. Also factor in the recovered time of your internal team. A service that costs £5,000 per bid and helps you win a £300,000 contract has delivered a clear return. A service that costs the same and contributes to repeated losses without any improvement in scores is not delivering value.
What is the most common red flag when evaluating a bid writing service?
The most common, and most damaging, is a reliance on generic templates. If your bids do not feel specifically written for each buyer and each contract, evaluators will notice. Scores on quality and methodology questions are particularly sensitive to generic responses. Always ask to see a sample of previous work, with client permission, before engaging a new service.