These three terms are used interchangeably and mean genuinely different things. The confusion is expensive, because a buyer who commissions one believing they are getting another discovers the gap after completion, when the growth case meets a commercial function nobody examined.
Commercial DD asks is this a good market to be in. Sales DD asks can this sales team sell. GTM DD asks can this business capture the growth in the plan — which includes the sales team and everything upstream and downstream of it.
Side by side
| Commercial DD | Sales DD | GTM DD | |
|---|---|---|---|
| Core question | Is the market attractive and is the company well positioned in it? | Can the sales function convert opportunity into revenue? | Can this business capture the growth in the plan? |
| Direction of travel | Outward, at the market | Inward, at one function | Inward, at the whole engine |
| Scope | Market size and growth, competitive set, customer perception, share | Pipeline, methodology, conversion, quota attainment, team, RevOps | Proposition and pricing, demand, sales, retention, and the people, data and cadence beneath them |
| Primary evidence | Market data, competitor analysis, customer and prospect interviews | CRM, quota and attainment records, sales team interviews | All of the above plus pricing realisation, usage, churn behaviour, operating rhythm |
| Typically run by | Strategy consultants | Sales leaders or specialists | Commercial operators across functions |
| Typical output | Market view and validated growth case | Assessment of sales capability and gaps | Capability verdict plus a sequenced, costed plan |
| Answers “why is growth stalling?” | Only if the cause is external | Only if the cause is in sales | Yes, including when the cause is somewhere nobody was looking |
| Timetable | 4–6 weeks | 1–3 weeks | 2–4 weeks |
Read the second-from-last row carefully. It is the practical distinction: a narrower scope can only find causes inside the scope it was given.
What a commercial due diligence does well
A commercial DD is the right instrument for external questions, and it is very good at them. How large is this market really, how fast is it growing, who else is in it, how do customers perceive this company against alternatives, is the share assumption in the model plausible.
Where it stops is at the company’s own capability. A CDD can establish that a market will grow at 12% and that the company is well regarded within it. It cannot establish whether this particular business has the pricing discipline, sales process and retention machinery to convert that into the model’s numbers, because the evidence for that sits in systems a market-facing study does not open.
This produces the most common gap in mid-market diligence: an attractive market, a well-positioned company, and a growth case that depends on commercial execution nobody assessed.
What a sales due diligence adds, and where it stops
Sales DD turns the lens inward and examines the sales function specifically: pipeline quality and coverage, methodology and whether it is actually used, win rates and cycle times, quota attainment and its distribution, team structure, tooling and RevOps discipline.
This is genuinely valuable and considerably cheaper than a full assessment. Its limitation is structural rather than a matter of quality: it examines the function where the symptom appears, which is frequently not the function where the cause sits.
A sales team missing its number may have a sales problem. It may equally have a proposition that has drifted out of fit, a demand engine delivering poorly qualified leads, a pricing model that makes deals hard to close, a churn rate that means new business is spent replacing losses, or a compensation plan paying for the wrong behaviour. Four of those five originate outside the sales function, and a sales DD will observe the symptom precisely while attributing it to the wrong cause.
If the sales team’s best performers are still winning consistently, the problem is probably in sales execution. If even the strongest sellers have stopped winning, the cause is almost certainly upstream, and a sales-only assessment will not find it.
Where GTM due diligence sits
A GTM due diligence covers the whole revenue engine and is explicitly designed to locate causes rather than catalogue symptoms. It assesses the proposition and whether the market still wants it, how demand is created, how interest converts, whether customers stay and grow, and whether the whole thing runs on process and data rather than on individual effort.
The reason for the breadth is not thoroughness for its own sake. It is that commercial problems interact, and a scope narrow enough to be efficient is usually narrow enough to miss the interaction. Assessing all of it is what allows a finding to be identified as a cause rather than a consequence.
The second difference is the output. A CDD produces a market view; a sales DD produces a capability assessment. A GTM DD is only useful if it produces a sequenced plan with owners, and that is a deliberate design choice: an assessment nobody can act on has not finished the job.
Which one do you need?
The question that resolves it is where the growth in your model comes from.
- Growth comes mostly from the market expanding. The company holds share in a rising market, with no material change assumed in pricing, win rates or retention. A commercial DD is likely sufficient.
- Growth depends on the company performing better than it does today. Higher win rates, better pricing, lower churn, a new segment. Commercial capability is the binding constraint, and neither a CDD nor a QoE tests it. This is the case for a GTM DD.
- You have a specific, isolated question about the sales function. A new CRO is being hired, or the sales team is the known issue and the rest of the engine has recently been assessed. A sales DD is proportionate and faster.
- The business is early, founder-led and pre-process. None of the three fits well. A focused proposition and traction review is more useful than any of them.
In practice, a commercial DD and a GTM DD are complements rather than alternatives: one establishes that the opportunity is real, the other establishes whether this business can take it. Running both is common on larger transactions and they overlap far less than people expect.
Frequently asked questions
What is the difference between sales due diligence and commercial due diligence?
A commercial due diligence looks outward at market attractiveness, competitive position and customer perception. A sales due diligence looks inward at the sales function specifically: pipeline, methodology, conversion, attainment and team. They answer different questions and neither covers the whole revenue engine.
Is GTM due diligence the same as sales due diligence?
No. A sales DD assesses the sales function. A GTM DD assesses the entire commercial engine, including proposition, pricing, demand generation, retention and the operating infrastructure. The distinction matters because the cause of a sales problem is frequently upstream of sales.
Do I need both a commercial DD and a GTM DD?
It depends where the modelled growth comes from. If it rests on the market expanding, a commercial DD may be enough. If it rests on the company executing better than it does today, that assumption needs a capability assessment, which a market-facing study does not provide.
Which is fastest?
A sales due diligence, typically one to three weeks because the scope is narrow. A GTM due diligence runs two to four weeks, and a commercial due diligence four to six because primary market research takes time.
Ready to aim higher?
If you are unsure which scope answers your question, we would rather talk it through than sell you the widest one.