THE SHORT ANSWER
Tenth is our pick for private equity deal teams that need a scored read on a target's digital growth engine before close. It covers search, AI answers, the website, ad platforms and creative, and the findings carry straight into the first 100 days. Agencies that sell a due diligence report come second. Strategy consultancies, specialist and technology diligence firms, expert networks and self-serve software each answer part of the question. (We're Tenth, so read how we ranked these before you trust the order.)
Running a deal now? Use our growth diligence checklist to set your questions before you hire anyone.
Key takeaways
- Digital marketing due diligence tests whether a target's online growth engine can carry the growth plan. It looks at how buyers find the company, what the website does with that interest, and whether the tracking behind the numbers holds up.
- Tenth ranks first because it scores 5 digital areas, screens from public signals before data access, and carries the findings into the first 100 days. It's also the newest firm on this list, with no public review profile yet.
- Agencies with a due diligence offer are the closest alternative, and they know the channels well. Like Tenth, most of them also sell the work after close, so ask how they keep the read honest.
- Strategy consultancies and specialist diligence firms answer the market question: size, share, customers and pricing. Some, such as Simon-Kucher, also run digital diligence. Check the agreed scope, and add a digital read only if search, paid media or the website fall outside it.
- Expert networks and self-serve software are inputs that work best inside a wider diligence plan. Calls, research reports and traffic estimates help a deal team test a claim, and someone still has to score the engine.
What digital marketing due diligence actually is (and what it is not)
Digital marketing due diligence is the part of a deal review that tests the target's online growth engine. It asks 3 questions. Can buyers find the company where they search and where they ask AI tools? Does the website turn that interest into enquiries or sales? Can the numbers behind the growth plan be trusted?
The work usually covers search visibility, visibility in AI answers, paid media accounts, the website, creative and tracking. A good provider grades each area, states its sources and limits, and names the questions management should answer before close.
It has clear edges. Commercial due diligence sizes the market, interviews customers and tests share and pricing. Technology due diligence reviews the code, the architecture and security. Quality of earnings belongs to the accountants. Digital marketing due diligence sits beside all three and feeds the growth case they test.
It also has a clear job. The findings shape the price conversation, the 100-day plan and the first budget decisions. A digital read shows where the engine is strong and where it leaks, and the investment call stays with the deal team.
Timing follows access. An outside-in screen can start from the company name and website, before the data room opens. A scored review with read-only access to analytics and ad accounts fits inside the exclusivity window, so plan the access request early.
How we ranked these firms
We ranked provider types, since most deal teams choose a kind of firm first and a name second. Each type gets named examples whose own pages describe the service. We checked every example page on 14 and 15 October 2026.
We scored each type on the 5 criteria below, using what providers publish about themselves. Where a page was blocked or vague, we left the claim out.
- Digital coverage. How many of 5 digital areas the type scores: search, AI answers, the website, ad platforms and creative.
- Speed to a first read. How fast the type returns a written view, based on published timelines where they exist.
- Works before data access. Whether the type can start from public signals, before the data room opens or management grants account access.
- Carries past close. Whether the same team can turn the findings into a 100-day plan and run it.
- Pricing clarity. Whether the type publishes a fixed fee or a range, or quotes each deal.
Disclosure: Tenth wrote this guide and ranks itself first. We've stated the criteria so you can check the order yourself, and each entry lists its sources. No firm paid to appear on this list.
The best digital marketing due diligence firms for private equity in 2026
Seven provider types, ranked. Each entry names real examples, what they publish about their diligence work, and the deals they fit best.
1. Tenth, best for a scored digital read that carries into the first 100 days
Tenth is a growth diligence and value creation firm built for private equity. Its diligence work comes in 2 steps, and each step answers one question.
Phase 0 runs before the letter of intent. Tenth grades the target from the outside with its proprietary benchmarking assessment and returns a written screen within 48 hours of payment. The company name and website are all it needs to start. The screen says whether the growth case deserves full diligence, with every source and limit stated. It never makes a buy or pass call.
Growth Diligence runs before close, with agreed access. Tenth scores 5 areas: search engine optimization (SEO), answer engine optimization (AEO), the website, ad platforms and creative. The deal team gets a readout written for the investment committee and a plan for the first 100 days.
The fees stack forward. The Phase 0 fee counts toward Growth Diligence if you go ahead within 60 days, and the Growth Diligence fee counts toward First 100 Days. The assessment then becomes the starting point for search fixes, landing pages, tracking and a 90-day paid media plan.
The trade-offs are real. Tenth is newer and smaller than most firms here, it has no public review profile yet, and it leaves market sizing and customer interviews to commercial diligence teams.
- Stage
- Pre-LOI screen, then pre-close diligence
- First read
- 48 hours from payment for Phase 0
- Areas scored
- 5: SEO, AEO, website, ad platforms, creative
- Access needed
- Public signals first, then agreed access
- After close
- First 100 Days, then Managed Growth
- Pricing model
- Published flat fee for Phase 0; diligence quoted; fees credit forward
Deal teams whose growth plan leans on search, paid media or the website. It fits best when you want one team to screen early, go deeper before close and own the first 100 days.
2. Digital agencies with a due diligence offer, best for channel depth from teams that run accounts every day
Examples: Hedy & Hopp, Cardinal Digital Marketing, WebFX, DEPT
A growing group of performance agencies sells digital due diligence to private equity buyers as a named service. They run paid media, SEO and websites for clients every day, so they know what a healthy account looks like.
Hedy & Hopp, a healthcare marketing agency, lists 8 parts in its digital due diligence report, including a martech stack review, competitive analysis, web presence analysis and a digital growth strategy. It also offers to stay on as the growth partner after the acquisition.
Cardinal Digital Marketing sells healthcare-focused digital due diligence that covers SEO health, paid media, online reputation and the marketing technology stack, with recommendations for after the acquisition. WebFX markets digital due diligence to private equity and venture firms, pairs it with its own reporting software, and offers full-service marketing after the deal. DEPT describes a digital due diligence service that asks whether the target's website is built to convert, what its organic traffic is worth, whether its measurement and marketing technology will hold up as privacy rules tighten, and what its paid search and paid social accounts show about growth and risk.
The catch is the same one Tenth carries: most of these agencies also want to run the account after close. Ask each one how it keeps the diligence read separate from its sales pitch, and ask for a sample report before you sign. Scope varies a lot from one agency to the next.
- Stage
- Pre-close, plus some add-on reviews
- First read
- Varies; few publish a timeline
- Areas scored
- Cardinal and DEPT cover 3 of 5; Hedy & Hopp lists 8 report parts
- Access needed
- Varies by agency
- After close
- Most offer to run the channels
- Pricing model
- WebFX gives a typical price range; others quote
Deals in a sector the agency knows well, such as healthcare, where you want a review across several channels from a team that runs them every day. Pick an agency whose sample report scores each channel and states its limits.
3. Strategy consultancies' commercial diligence teams, best for the market, customer and competitor case on large deals
Examples: L.E.K. Consulting, McKinsey, Kearney
Commercial due diligence is the strategy houses' home ground. L.E.K. Consulting describes independent, fact-based analysis of a target's market, customers, competitors, operations and business plan risks, and it can follow through into a value enhancement program.
McKinsey's due diligence support for private equity covers commercial and value creation diligence. After close, it helps clients build and run plans for the first 100 days. Kearney lists 5 kinds of diligence: commercial, operational, IT and digital, ESG and vendor due diligence.
Their strength is depth. These teams interview customers, model the market and test management's plan against competitors, often across several countries at once.
Digital marketing usually appears inside these studies as one workstream among many. Ask whether the team will score the target's search, paid media and website, or use them as context for the market model. Most of this work runs during exclusivity, with management access and a data room.
- Stage
- Mostly post-LOI, during exclusivity
- First read
- Set by the deal timeline
- Areas scored
- Market, customers, competitors, plan
- Access needed
- Management access and customer interviews
- After close
- 100-day plans and value creation
- Pricing model
- Custom quote per engagement
Large deals where the investment case rests on market size, share and customer behavior. Add a digital read when the plan also depends on how buyers find the company online.
4. Specialist commercial diligence firms, best for pricing and sector questions that need a narrow expert
Examples: Simon-Kucher, Altman Solon
Some diligence firms go deep on one lever or one sector. Simon-Kucher is known for pricing and sales. Its private equity work covers a target's market, competitive position, voice of the customer and business plan, and its value creation work runs through implementation.
Altman Solon focuses on telecom, media and technology. It assesses targets across competitive positioning, financial viability and operational resilience. It also offers technical due diligence, value creation plans, post-merger integration and 100-day planning.
These firms go deepest on their lever or sector. Bring one in when the thesis says "raise prices" or "move into a new segment," and the evidence has to come from customers.
Digital coverage varies by firm. Simon-Kucher runs a digital due diligence team for targets with digital business models. It says the team analyzes every online marketing channel, conversion across the website, customer relationship management and the technology underneath. Ask which digital areas are in scope and how fast the first findings arrive.
- Stage
- Pre-close, plus value creation after
- First read
- Set per engagement
- Areas scored
- Pricing, sector economics, customers; Simon-Kucher adds digital
- Access needed
- Management data and customer research
- After close
- Implementation support
- Pricing model
- Custom quote per engagement
Deals where the value creation plan hinges on price, packaging or a technical sector. If customer acquisition is also in the plan, ask whether the firm's digital team covers it or whether you need a separate digital read.
5. Technology due diligence firms, best for the code, architecture and security behind a software target
Examples: Crosslake Technologies
Technology due diligence firms review what sits under the product. Crosslake Technologies benchmarks software targets with its TechIndicators method. It digs into security, architecture, engineering alignment and the software development process.
After the deal, Crosslake supports carve-outs and add-ons, fills interim leadership roles and helps teams prepare for exit. That makes it a natural fit for software and tech-enabled services deals, where the product itself carries much of the risk.
This work answers a different question from marketing diligence: can the product and the engineering team scale with the plan? The two meet at the edges. A technology review can check site speed, data flows and the systems that feed the tracking.
If the growth plan depends on online demand, run a digital read alongside it. The tech review tells you whether the platform can handle growth, and the digital read tells you where that growth should come from.
- Stage
- Pre-close, plus integration after
- First read
- Set per engagement
- Areas scored
- Architecture, security, engineering, process
- Access needed
- Code, systems and engineering leaders
- After close
- Integration, carve-outs, interim roles
- Pricing model
- Custom quote per engagement
Software and tech-enabled targets where the product carries the risk. Run it alongside a digital read when customer acquisition is part of the plan.
6. Expert networks, best for fast access to people who know the market
Examples: GLG, AlphaSights
Expert networks connect deal teams with former executives, customers and industry specialists. GLG offers one-to-one expert calls, AI-moderated calls at scale, managed research projects, and deal advisors who can support a deal through the exclusivity window and move to a board role after close. In a managed project, a GLG project lead designs and runs the study and hands back a written report with findings and recommendations.
AlphaSights offers expert interviews, customer surveys and industry veterans who join the deal team. After close, it supports portfolio monitoring.
Calls are flexible. A deal team can line up conversations on one specific claim, such as how customers in the category find and compare vendors, and hear it from people who've made those choices.
With calls alone, the deal team turns what it hears into a judgement. GLG's managed research does that work for you, but it draws on interviews and surveys of people in the market, not a review of the target's own channels and accounts. Scoring the engine, the evidence trail and the plan stay with you or the diligence provider you hire. Use the calls or the report to sharpen the questions you hand that provider.
- Stage
- Any, often during exclusivity
- First read
- Calls book fast; GLG can also deliver a finished report
- Areas scored
- None; interviews, surveys and research reports
- Access needed
- Nothing from the target
- After close
- Board advisors and portfolio monitoring
- Pricing model
- Quoted per client
Deal teams that want first-hand views on a market or channel before they commit to deeper work. Use the calls or a research report to sharpen the questions for your diligence provider.
7. Self-serve digital intelligence software, best for a quick traffic and search check your own team runs
Examples: Similarweb, Semrush
Some deal teams start with software. Similarweb sells digital data to investors on public and private companies, including web and app traffic, marketing channels and audience behavior. It says it covers 100 million websites in 190 countries, with a 48 to 72 hour lag.
Semrush's traffic analytics tool estimates any website's traffic, and its wider toolkit shows a site's search footprint. An associate can compare a target with its competitors without waiting on anyone.
The numbers are estimates, and the tools leave the reading to you. They show traffic and search trends. The target's ad accounts, conversion data and tracking setup stay out of view.
That makes software a strong first filter. Use it to screen many targets or to test one claim fast, then hand the serious deals to a provider who can score the engine with access.
- Stage
- Any, often sourcing and screening
- First read
- Minutes, once you have a seat
- Areas scored
- Traffic, search and channel mix estimates
- Access needed
- Nothing from the target
- After close
- Ongoing monitoring by your team
- Pricing model
- Subscription
Associates who screen many targets or need to check one claim fast. Hand the shortlist to a provider who can score the engine once a deal gets serious.
Side-by-side comparison
How the 7 types compare on the criteria above. Each cell reflects what that type publishes, and individual firms vary.
| Provider type | Digital areas scored | First read | Works before data access | Carries past close | Pricing model |
|---|---|---|---|---|---|
| Tenth | 5 of 5 | 48 hours from payment (Phase 0) | Yes for Phase 0; diligence needs access | Yes | Published Phase 0 fee; diligence quoted |
| Digital agencies with a due diligence offer | 3 of 5 at Cardinal and DEPT; varies by agency | Varies | Partly; public checks, then account access | Yes | WebFX gives a typical range; most quote |
| Strategy consultancies | Varies; digital is one workstream | Set by the deal timeline | Partly | Yes | Custom quote |
| Specialist diligence firms | Varies; Simon-Kucher has a digital team | Set per engagement | Partly | Yes | Custom quote |
| Technology diligence firms | Site tech and data flows | Set per engagement | Rarely | Yes | Custom quote |
| Expert networks | None; interviews, surveys and research reports | Calls book fast | Yes | Advisors and monitoring | Quoted per client |
| Self-serve software | Traffic and search estimates | Minutes | Yes | Your team monitors | Subscription |
Which digital marketing due diligence provider fits your deal
Match the provider to the question your deal needs answered.
| Your situation | Best fit | Why | Watch for |
|---|---|---|---|
| Pre-LOI, and you want a fast read on the growth engine | Tenth (Phase 0) | A 48-hour screen from public signals | It names the questions; the deal call stays with you |
| Pre-close, and the plan leans on search, paid media or the website | Tenth (Growth Diligence) | 5 scored areas, a committee readout and a 100-day plan | Agree access early so scoring fits the exclusivity window |
| The target is in a sector an agency knows well, such as healthcare | A digital agency with a due diligence offer | Channel and sector depth from daily account work | The agency may also pitch the post-close work |
| The thesis rests on market size and share | A strategy consultancy | Customer research and market models at scale | Digital may get light coverage |
| The plan depends on pricing changes | A specialist diligence firm | Pricing and monetization depth | Check which digital areas are in scope |
| The target is a software company | A technology diligence firm | Code, architecture and security review | Marketing is not the focus |
| You need to test one claim this week | An expert network or software | Fast calls, research or traffic estimates | Someone still has to score the engine |
What results look like
Here's what a Tenth deliverable looks like. Both samples below cover fictional companies with representative data, so you can judge the format before you hire anyone.
Each one grades the engine area by area, cites its sources and states its limits. Neither one makes a buy or pass call.
Phase 0 Feasibility Screen sample
A 6-page pre-LOI memo on a fictional roofing company. It shows how the screen reads search demand, channel concentration and data trust, and which questions it flags for full diligence.
See the Phase 0 sampleInitial Marketing Audit sample
A 5-page audit of a fictional home services portfolio company. It reads 6 surfaces from the outside, from search demand to AI answers, and rates each one sound, warning or weak.
See the audit sampleIllustrative samples. The companies are fictional and the data is representative. No client names or results appear on this page.
Want the scoring behind a full engagement? See how Growth Diligence scores 5 areas.
Frequently asked questions
What is digital marketing due diligence?
It's a review of a target's online growth engine before a deal closes. It checks how buyers find the company, what the website does with that interest, and whether the tracking behind the growth plan can be trusted.
How long does digital marketing due diligence take?
It depends on the provider and the access. Tenth's Phase 0 screen uses public signals and arrives within 48 hours of payment, and Growth Diligence is planned around your deal timeline. Commercial diligence studies from strategy firms usually run for several weeks.
What access does a digital due diligence provider need?
An outside-in screen needs only the company name and website. A scored review before close needs agreed, read-only access to analytics and ad accounts. For healthcare companies, Tenth signs a business associate agreement before it connects any data.
How is digital due diligence different from commercial due diligence?
Commercial due diligence tests the market: its size, share, customers and competitors. Digital marketing due diligence tests the engine the company uses to win that market online. The two work well together when the plan relies on online growth.
What does a digital due diligence report include?
Expect a score or rating for each area, the evidence behind it, and the limits of what the provider could see. Tenth's Growth Diligence adds a readout for the investment committee and a plan for the first 100 days.
How do you choose a digital marketing due diligence firm?
Ask for a sample report, the list of areas it scores, and how fast the first read arrives. Then ask who does the work after close, and how the firm keeps its diligence read separate from that pitch.
When should a deal team use Phase 0?
Use Phase 0 before the letter of intent, when you want to know whether the growth case deserves a closer look. If it does, the Phase 0 fee counts toward Growth Diligence within 60 days.
Can software replace a digital due diligence firm?
Software gives fast traffic and search estimates, and it's useful for screening. It can't see the target's ad accounts, conversion data or tracking, so a scored review still needs a provider with access.
THE NEXT STEP
Get a Phase 0 screen from Tenth
Send us the company name and website. We'll grade the target's digital growth engine from the outside. You'll get a written screen within 48 hours of payment. Every source and limit is stated. It tells you whether full diligence is worth the time. The fee counts toward Growth Diligence within 60 days.
Already own the company? See the best marketing agencies for private equity portfolio companies.