Average customer value
Total revenue from a typical customer across the relationship. Include repeat and referral work if you can attribute it. This is usually higher than owners assume.
Guide
SEM Budget: How to Set and Split It
Most search engine marketing budgets are set by one of two methods: a percentage of revenue that somebody read in an article, or whatever last year was plus a bit. Neither connects to what a customer is worth or what the market costs, which is why so many budgets are simultaneously too large for what they are aimed at and too small to win it.
There is a more useful way to work it out, and it starts from the value of a customer rather than from the size of the company. This page walks through the arithmetic, the floors below which spending stops working, and how to divide money between paid and organic. It is written so you can do it yourself.
Why start from customer value rather than a revenue percentage?
The number that governs everything is what a customer is worth to you over the life of the relationship, and what proportion of that you can afford to spend acquiring them. A business where an average customer produces $400 once and a business where an average customer produces $4,000 over three years are playing completely different games, and a revenue percentage rule treats them identically.
Work out three figures before setting any budget. First, average customer value including repeat work, not just the first transaction. Second, the proportion of that you can spend on acquisition while leaving acceptable margin — for most service businesses this lands between ten and twenty-five percent. Third, your close rate on enquiries, because the cost of an enquiry and the cost of a customer differ by that factor and it is frequently a factor of four or more.
Acceptable acquisition cost
The share of that value you can spend and still make the work worth doing. Ten to twenty-five percent is common; lower in thin-margin work, higher where lifetime value is long.
Enquiry-to-customer close rate
If one in four enquiries becomes a customer, an affordable customer cost of $400 means an affordable enquiry cost of $100. Skipping this step is the most common budgeting error.
Market click cost
What clicks actually cost in your category and area. This decides whether your affordable enquiry cost is achievable or whether paid search is the wrong channel entirely.
Below what level does search ad spending stop working?
Search marketing has minimum viable amounts, and spending below them tends to produce nothing rather than proportionally less. In paid search the constraint is data: a campaign needs enough conversions per month for the platform to optimise and for you to distinguish signal from noise. Below roughly fifteen to twenty conversions monthly, an account stays in a permanent learning state and every decision is made on insufficient evidence.
For most local service categories that translates to something in the range of $1,000 to $2,000 a month in ad spend, higher in expensive markets and categories. In organic search the floor is different — it is about consistency over time rather than monthly volume. A small ongoing programme sustained for a year beats a large burst over two months, because the compounding only happens with continuity.
How should you split the budget between paid and organic?
The two channels have opposite cost curves and that is the whole basis for splitting between them. Paid search produces traffic immediately and stops the day you stop paying; its cost per acquisition is roughly flat forever. Organic takes months to produce anything and then continues producing after the work stops; its cost per acquisition falls over time.
A reasonable default for a business with an established site is somewhere near sixty percent organic and forty percent paid, with paid weighted toward the terms with the clearest immediate economics. A brand-new business usually inverts that for the first six to nine months, because it needs revenue before organic can mature. A business with strong existing rankings and a thin pipeline should weight the other way. The split is a function of how urgently you need revenue against how long you intend to be in business.
What should you check before increasing a budget?
More spend amplifies whatever the current system does, including its failures. Before adding money, confirm that enquiries are being answered promptly, that the tracking distinguishes genuine enquiries from noise, and that the site converts at a defensible rate. A business converting two percent of traffic that doubles its spend gets twice the traffic and the same two percent — whereas fixing conversion to four percent doubles results at no additional media cost.
The order matters and it is almost always the same: fix measurement first, because you cannot evaluate anything without it. Fix conversion second, because it multiplies everything downstream. Increase spend third, once you know what it is buying.
How do the numbers work for two businesses with the same revenue?
| Emergency plumbing | Kitchen remodeling | |
|---|---|---|
| Average customer value | $450 | $28,000 |
| Acceptable acquisition cost (15%) | $68 | $4,200 |
| Enquiry close rate | 1 in 3 | 1 in 8 |
| Affordable cost per enquiry | $23 | $525 |
| Viable if clicks cost $12? | Marginal — needs 50%+ conversion | Comfortably |
Straight answers
What do businesses ask about setting an SEM budget?
What percentage of revenue should go to search marketing?
The commonly cited range is five to ten percent of revenue for established businesses and more for those in growth, but the percentage is a sanity check rather than a method. It ignores customer value, close rate and what your market actually costs, which are the three things that determine whether a budget can work at all. Two businesses with identical revenue can have correctly different budgets by a factor of five. Use the percentage to check whether your calculated figure is wildly out of line, not to produce it.
How much of an SEM budget goes to management versus ad spend?
Management typically runs between fifteen and thirty percent of ad spend, with the proportion falling as spend rises because the work does not scale linearly. On smaller budgets a flat fee is more common than a percentage — ours starts from $300 a month — because a percentage of a small budget does not cover the hours the account genuinely needs. Be cautious of management priced purely as a percentage with no floor, since it creates an incentive to increase spend rather than to improve efficiency.
Should a new business spend on SEO or paid search first?
Paid search first, in most cases, then shift as organic matures. A new business usually needs revenue before it can afford to wait the six to twelve months that organic search takes to produce meaningful traffic. Paid search produces enquiries within days, which funds the organic work. The mistake is treating that as permanent — a business still spending entirely on paid at year three is renting all of its traffic, and its acquisition cost will never improve. The transition should start once the first organic positions begin producing.
How do I know if my current SEM budget is working?
Compare cost per acquired customer against your calculated affordable acquisition cost, and track whether that cost is rising, flat or falling over time. A programme that is working shows a falling blended acquisition cost as organic contributes more and paid targeting tightens. If you cannot calculate cost per acquired customer at all, that is the first problem to solve — not the budget. Reporting that shows impressions, clicks and conversions without connecting them to actual customers cannot answer the question, and a great many monthly reports are exactly that.
Is it better to spend heavily for a short period or modestly over a year?
For organic search, modestly over a year, without much ambiguity — authority and content depth compound with continuity and a two-month burst produces very little that lasts. For paid search the answer depends on why you are spending: sustained spend builds usable data and lets targeting improve, whereas a burst makes sense for genuine seasonality, like an HVAC contractor ahead of a season turn. What rarely works is an unplanned stop-start pattern, which resets learning phases and wastes the optimisation already paid for.
Which pages should you read next?
Start with a clear read
What should your business actually spend on search ads?
A free analysis that calculates your actual customer value, what a lead can cost you, and whether your current budget is aimed at something winnable.