SEO agency vs. in-house vs. consultant: how to choose

Most business owners and marketing leaders I work with have, at some point, asked some version of the same question: should we hire an SEO agency? Bring on a consultant? Add someone in-house? Some combination of the three?

It’s a fair question, and it doesn’t have a single right answer. Different setups make sense at different stages, team sizes, and goals. The wrong choice is rarely a disaster, but it almost always costs you time, money, and momentum you’d rather have spent elsewhere.

In this post I’ll walk through each of the three options: what they’re good at, what they’re not, and how to figure out which one fits your business right now. I’ll also share a few specific patterns I’ve seen come up over and over again across the businesses I’ve worked with, because the structural strengths and weaknesses of each model tend to show up in pretty consistent ways.

For context: I’ve been doing SEO for 20 years, the last 12 of those running my own independent SEO consultancy. Most of my clients are mid-market companies and growing SMBs, and my view is admittedly shaped by what’s worked (and what hasn’t) for that profile of business. If you’re at a Fortune 500 with a 30-person in-house SEO team, your situation is different and a lot of what follows won’t apply. For most other people reading this, it probably will.

Quick definitions before we get into it

In-house SEO means hiring someone (or several people) who works for your company full-time, focused specifically on SEO. Could be a single SEO manager. Could be a full team with specialists in technical, content, and analytics.

An SEO agency is an outside company with multiple people on staff: typically a strategist or two, an account manager, content writers, technical SEOs, link builders, and so on. You work on a retainer or a project basis, and the agency assigns people from their bench to your account.

An independent SEO consultant is a solo practitioner (sometimes a very small team) who works directly with your business. Senior-level expertise without an agency’s overhead. But without an agency’s team. Usually retainer-based, sometimes project-based.

Each model has real strengths and real weaknesses. Let’s go through them.

Option 1: SEO agencies

Agencies are good at one thing: scale. If you need lots of pages produced, multi-channel coordination (SEO + content + paid + social all under one roof), or significant production capacity an internal team can’t handle, agencies can deliver in ways that consultants and small in-house teams simply can’t match.

They’re also a reasonable choice for enterprise companies where the buying process favors a single vendor with depth on staff and a recognizable brand name.

But the agency model has structural issues that repeat across clients, particularly for mid-market companies that aren’t quite at agency scale. Most of the clients who come to me are coming off an agency relationship that didn’t work, and the same patterns repeat. A few of the most common:

Rotating account managers

One of my recent clients put it like this: “We were assigned a new account manager about every six months, and that presented its own hurdles, with the new managers having to get up to speed on our account each time.”

This isn’t bad luck. It’s the agency staffing model. Account managers churn, get promoted, switch agencies, or leave the industry. Each transition costs you weeks of momentum while the new AM gets up to speed on your business, your goals, and the work that came before.

Slow turnaround and under-servicing

Another recent client described offboarding their previous agency this way: “We recently offboarded an agency who didn’t turn any deliverables around within reasonable timeframes. After providing them with the information they needed to get started, they waited over a week to begin working on anything while we had paid them for onboarding and our first month’s retainer.”

Your account is one of many at an agency. The math is obvious: the clients getting full attention are usually the ones who got there by being the squeakiest wheel.

Deliverables that don’t get done

Same client’s discovery questionnaire, when I asked what they wished their old SEO had done for them: “Literally anything. They didn’t deliver one output for us.”

That’s an extreme version, but a milder version of this comes up all the time. Strategy decks get presented in monthly calls; the actual execution lags or disappears. Audits get delivered, fixes don’t get implemented. The pitch was about outcomes; the day-to-day reality is about deliverables.

Junior staff doing the work that senior staff sold

The senior SEO who pitched you is often not the person doing the day-to-day work on your account. That work gets delegated down, to a less experienced strategist, a content team, or a technical SEO juggling multiple accounts. You hired the agency because of the partner you met. You’re getting the analyst they assigned.

And the deeper problem with that staffing model is the lack of senior oversight on technical decisions. One client I used to work with eventually outgrew what I could offer as a solo consultant (they were expanding into video, podcasts, and channels I don’t do) and moved to an agency. For three years after the transition, the blog posts I’d originally written were still the top traffic-driving pages on their site. Then one day I noticed all those pages were returning 404 errors. The agency had restructured the blog URLs to add category folders but hadn’t implemented any 301 redirects. I emailed the founder; they got it fixed within hours.

The fix itself was easy. The mistake happening in the first place is the part worth thinking about. That’s the kind of error that almost never occurs when a senior SEO is making the call, because senior SEOs know to check for it. It’s also the kind of mistake that costs companies months of organic traffic, and often, no one inside the company even notices.

Slow adaptation to AI search

That same structural lag shows up most visibly right now with AI search. The agencies that have adapted quickly to ChatGPT, Gemini, Perplexity, and AI Overviews are the ones whose senior people stayed close to the work. The ones still treating AI visibility as “we’ll figure that out next quarter” are usually the ones running on production templates and approval committees, neither of which moves at the speed AI search actually requires. Whether your agency can credibly say what they’re doing differently for AI search this year is a useful read on which side of that divide they’re on.

The cost

Good SEO agencies typically charge $10,000 a month and up because they have to support a staff, account management, sales and marketing overhead, and office costs on top of the actual work on your account. A solo consultant carries none of that, which means comparable scope tends to land around half the cost. This isn’t positioning. The cost difference is structural. The agency model carries more weight in the back office, which gets passed along to clients.

To be clear: there are excellent agencies out there. If you’re at the right stage for one (enterprise, multi-channel, significant production volume), they can be a fantastic partner. But the agency model itself creates these failure modes more often than the other two models do, and most of the businesses I work with aren’t at the stage where an agency’s strengths outweigh those tradeoffs.

Option 2: In-house SEO

In-house is the right call for a specific kind of business, one where SEO is core to revenue, there’s enough internal volume of work to justify a full-time hire (or several), and there are mature teams in engineering, product, and content for that hire to collaborate with.

When you have all three of those things, in-house is genuinely the best setup. A strong internal SEO becomes embedded in how the company operates. They build institutional knowledge over time. They know your business better than any outside partner ever could, because they live it every day.

The problem comes when companies try to make in-house work in a context where the conditions aren’t met.

Where it breaks down

Most often I see this with mid-market companies and growing SMBs who think hiring “one SEO person” will solve the problem. The person gets hired, and within a few months they’re drowning. They’re trying to handle keyword research, content briefs, technical audits, reporting, stakeholder management, link building, and now AI search experimentation across ChatGPT, Gemini, Perplexity, and AI Overviews, all by themselves, often without anyone above them who’s actually done SEO before. The good ones burn out and leave within 18 months. The not-so-good ones stay and don’t move the needle.

The cost reality

There’s also the cost reality. A solid in-house SEO with 3-5 years of experience runs $80,000 to $100,000 in base salary. Senior or director-level talent is closer to $120,000 to $160,000 and up. Add benefits, taxes, equipment, and the software stack they’ll need to do the work, and that single hire usually lands somewhere between $110,000 and $180,000 all-in. That’s a meaningful budget commitment for a result that lives or dies on whether the rest of the conditions above are met.

The honest gut check

If you’re a 30-person company thinking about hiring an SEO manager, the honest gut check is this. Do you have a head of marketing who can mentor them? Do you have a content team for them to work with? Is there enough work to keep them busy full-time? If the answer to any of those is no, you don’t need a hire. You need a partner.

Option 3: Independent SEO consultant

Independent consultants tend to be the right fit for businesses in a specific window: mid-market companies and growing SMBs that need senior SEO expertise but don’t have the volume of work or the budget overhead to justify an agency relationship. Companies where speed and direct decision-making matter. They want the person doing the work to also be the person they talk to.

What consultants are good at

Direct relationship with the practitioner. No layered context loss between strategist, account manager, and executor. Because all three are the same person.

Senior-level thinking on every call, every report, every recommendation. You’re not paying agency margin to subsidize junior staff doing the actual work.

Faster pivots when something changes. This matters in normal times. It matters more right now. AI search is reshaping how visibility works, and the answer to what to do about it changes faster than agency approval cycles can handle. When I want to start tracking ChatGPT citations for a client, test a new schema approach, or pivot a content strategy mid-quarter, I can decide and implement in the same week. No committee approval, no internal sign-off, no agency leadership debating whether it’s billable.

A partner who can push back honestly. Consultants don’t have an account manager whose bonus depends on you renewing. We have direct relationships, which means we can give you real pushback when you’re wrong without worrying about losing the account.

The tradeoffs

Capacity is finite. One person can only do so much. If you need significant production volume (50 content pieces a quarter, an international rollout, multi-vendor coordination at scale), a consultant can’t be your only resource.

Consultants can’t replace a full marketing department. We’re SEO specialists. We don’t run paid media. We don’t manage social. (In my case, we don’t produce video.) If you need broader digital marketing capability, you’ll need a consultant plus something else. Not a consultant alone.

Vetting matters more than with an agency. With an agency, the brand is at least some safety net. Even if you don’t love your specific account team, you can usually escalate. With a consultant, you’re trusting one person. Their references, their portfolio, their actual approach: all of it needs to hold up.

One of my longer-running clients came to me after roughly four years with an agency. Over those four years, their organic traffic had grown to about 500 visits a month. By the time we wrapped, we’d grown it to 56,000 visits a month at peak. That’s not because I’m magic. It’s because for a mid-sized business with a defined target audience, focused senior attention usually beats scaled attention from people who barely know the account.

How to figure out what fits your business

Most of the comparison content online frames this as “X is objectively better than Y.” That’s usually wrong. The better question to ask is: which model is structurally matched to my business, right now?

A few honest questions to walk through:

1. Do you have someone internal who owns SEO daily? If yes, an agency or a couple of freelance specialists can supplement what they do. If no, you probably need a consultant who can own it for you.
2. Is SEO a core revenue channel for you, and is the company large enough to support a senior FTE plus the team they’d need around them? If yes to both, in-house. If no to either, external.
3. Do you need scale, or seniority? Lots of pages, lots of channels, lots of production volume points to an agency. Sharp strategic thinking, fewer but better moves points to a consultant.
4. How important is direct access to the person actually doing the work? Very important points to a consultant. Less important means an agency works.
5. Is the partner you’re evaluating fluent in AI search? Ask any agency, in-house candidate, or consultant what they’re doing differently for ChatGPT, Gemini, Perplexity, and AI Overviews this year. If they treat it as a separate service (or hedge with “we’re still learning”), you’ve learned something useful. Search has changed; the people you hire to handle it should have changed with it.
6. Have you been burned before by an agency that disappeared or under-delivered? If yes, that’s worth weighing. But the answer isn’t “all agencies are bad.” It’s “make sure your next partner’s model actually matches your needs.”

For most mid-market companies and growing SMBs, the honest answer ends up being a consultant. Consultants aren’t objectively better than agencies. Plenty of agencies run circles around solo consultants in some markets. The consultant model just fits how those businesses operate better than the alternatives do.

The bottom line

There are great agencies. There are great in-house SEO teams. There are great independent consultants. None of them is great in every context.

The right question isn’t “who’s the best.” It’s “who fits where my business actually is right now?” Ask yourself the questions above honestly, and the right model usually becomes clear.

If you’re weighing whether an independent SEO consultant might be the right fit for your business, I’d be happy to chat. Take a look at how I work with clients, or send me a note and we’ll figure out together whether we’re a fit.