How much you should spend on Google Ads, worked out from the bottom up

Work your Google Ads budget out from the leads you want, using simple arithmetic: the number of leads you need each month, multiplied by the clicks it takes to produce one lead, multiplied by the cost of a click in your market. That gives you a media budget grounded in your own targets, and it usually lands somewhere different from the number that felt affordable.

The rest of this page works the example, explains why starting too small produces nothing, gives you my rule for when a management fee is justified, and covers the two situations where the right spend is zero.

What is the arithmetic?

Budget equals target leads, times clicks per lead, times cost per click.

Clicks per lead is the inverse of your website conversion rate: if one visitor in ten fills in your form, you need ten clicks per lead. Cost per click (CPC) you can estimate from Google's Keyword Planner, or from a short live test. Here is a worked example with clearly hypothetical numbers, so you can see the shape of it.

Budget matches the target

Target leads per month20

Clicks per lead (1 in 10 converts)10

Example cost per clickR60

R12,000 a month in media buys roughly 200 clicks and a fair shot at 20 leads

Budget starves the same target

Target leads per month20

Same clicks per lead10

Budget set by feelR2,000

About 33 clicks a month, roughly 3 leads, and a verdict of 'ads don't work' that the maths predicted in advance

One refinement: your actual CPC depends partly on Quality Score, which is Google's rating of your expected clickthrough rate, ad relevance and landing page experience. Low scores raise the cost of every click, so a weak landing page inflates the whole equation.

Why does starting too small produce nothing?

Because Google's automated bidding, called smart bidding, optimises toward whatever your conversion action counts, and it degrades without conversion data. A budget that buys one or two clicks a day produces a trickle of conversions, the algorithm never gets enough signal to learn who your buyers are, and it re-learns slowly after every change you make in frustration.

So a tiny budget run for six months tells you almost nothing, while a proper budget run for two or three months gives you a readable answer. If the bottom-up number is beyond you right now, shorten the test rather than shrinking the daily spend, or hold off entirely until it fits.

When should you pay a management fee?

My rule: below roughly R7,500 a month (about $400 to $500) in media budget, pay no management fee at all. Specialist management in South Africa commonly costs R6,500 to R10,500 a month, and percentage fees commonly land somewhere between 10 and 20 percent of spend. On a R5,000 media budget, a typical fee doubles your total cost before a single extra click arrives. At that scale, run it yourself with a simple structure, or buy a few hours of help to set it up properly.

I have published the full fee landscape for South Africa in what Google Ads management costs in South Africa, and for buyers abroad in the UK, US and Australia version.

The media budget you are consideringR3 000 to R7 500

What specialist management costsR6 500 to R10 500

Below roughly R7,500 a month in media, the fee rivals the budget it manages. At that size a once-off setup done properly beats paying anyone a retainer, which is the only honest answer even though it is the one that costs me the work.

When should you spend nothing at all?

Two situations, and both are common.

First, when there is no working measurement on the site. Fix measurement before judging campaigns, and certainly before funding them. One account I took over in 2026 counted 75% of clicks as conversions because the tracking tag fired the moment the page loaded, and every budget decision ever made on those numbers was fiction. The three checks that tell you whether your own numbers are real are in the three receipts, and if your account already reports conversions while the inbox stays quiet, start with Google Ads shows conversions but I get no leads.

Second, when the offer itself does not convert. If your site already gets visitors from search, social or referrals and almost none of them enquire, Google Ads will buy you more of the same silence at R60 a visit. Fix the page and the offer first, then pay for traffic.

What should you do next?

Run the arithmetic with your own targets and a realistic CPC, check the result against the R7,500 floor before agreeing any fee, and confirm your measurement passes the three receipts before the first rand goes in. If the number justifies hiring help, how to brief a Google Ads freelancer covers what to put in the brief and the one test that separates candidates who can prove results from candidates who can only describe them.