Should you hire an SEO agency or train someone in house
Compare an SEO retainer against building the skill internally on real total cost implementation capacity and the single metric that decides either model.
The comparison most owners make first
You have a marketing executive who is capable and willing. An agency has quoted a monthly figure. The instinct is to put the retainer beside the salary and pick the smaller number. That comparison is wrong in both directions and it is the reason this decision is so often reversed within a year.
The real difference is not price. It is what each model does with your implementation capacity and how much of the discipline you actually need every month.
What each route costs and what is excluded
An agency retainer excludes your developer time your content approvals and your own subject matter knowledge. Recommendations arrive as instructions and somebody inside your business has to act on them. It excludes the writing of anything only you can write. An SEO retainer covering fifty or more keywords carries a published rate on its service page and GST applies at 18% on the fee. Salary carries no GST which makes the gross cost comparison uneven. Whether your business can take credit for that tax depends on your registration and a qualified professional should confirm it for your situation.
In-house excludes the tooling. Rank tracking a site crawler backlink data and a log analyser are annual licences and they are priced for agencies rather than for one user. It also excludes the training itself and the cost of a single-threaded role. One person holding the entire discipline means it stops when they take leave and it leaves with them when they resign. Budget for both or the comparison flatters the internal route.
Which model fits and when neither does
Hire neither if you cannot change a page on your own website within a week. That is the test and it is not a rhetorical one. An agency will deliver findings into a queue nobody services and an internal hire will spend their first year chasing a developer who reports to someone else. Fix publishing access first. It costs far less than either option and without it both fail.
In-house suits businesses with deep technical subject matter and continuous publishing. A hospital group a software firm or a manufacturer with hundreds of specifications needs someone who understands the product well enough to write about it. That knowledge takes long enough to acquire that outsourcing it repeatedly is wasteful.
A retainer suits businesses needing several disciplines part-time. Technical work content planning link acquisition and reporting are different skills and no single junior hire holds all four. A retainer buys a slice of each. It also suits businesses where organic search matters but does not justify a full salary. The split model works better than most owners expect. The agency handles technical work and off-site acquisition while the internal person owns publishing and keeps the subject matter accurate.
What each actually involves month to month
A retainer at this scope runs a repeating cycle. Keyword and page mapping maintained as the site changes. On-page work on a defined set of pages. Technical issues found and specified for your developers. Off-site work to earn links and mentions. Then reporting that compares movement against the previous period.
Training someone internally means they learn on your website. That is the part nobody says out loud. Early mistakes land on your live pages and some of them take months to show. Give them a structured programme a budget for tools and someone external to review their work quarterly. Without review a self-taught practitioner repeats the same misunderstanding for a year.
In either model insist on a written monthly priority list limited to a handful of items. Long documents are a symptom of work being described rather than done.
How to judge whichever you pick
The flattering metric is volume of deliverables. A forty page audit a long keyword sheet and a detailed monthly report all feel like value and none of them changed your website. Report length is the easiest thing in this industry to inflate.
The metric that matters is implementation rate. Count the recommended changes that actually went live each month. Then track non-branded organic sessions and the enquiries or orders they produce. If implementation is low the model is not the problem and changing providers will not help.
The common mistake
The expensive error is treating this as a channel to be bought rather than a publishing commitment to be funded. Businesses sign a twelve month retainer approve nothing and then conclude that organic search does not work for their sector. They paid for a year of advice and shipped two months of it.
The internal version of the same error is hiring one junior and expecting them to produce technical fixes written content and links at once. They will do the part they enjoy. The rest quietly does not happen and you will not find out for three quarters.
What neither model can promise
No agency and no employee can promise rankings traffic or a date by which either arrives. Search engines change how they rank without notice and your competitors are investing at the same time. What either model can commit to is defined work delivered at a stated cadence with findings you can inspect. Judge the commitment on the work and the implementation rather than on a forecast nobody controls.
This guide explains how something works. It is not legal, tax or financial advice, and rules change. Confirm anything regulatory with a qualified professional before you act on it.