How much you need to spend on Meta Ads before the result means anything

The question always arrives the same way: "how little can I start with?" And the honest answer isn't a number, it's another question — start advertising, or start knowing whether it works? Those aren't the same thing, and they don't cost the same.

You can start advertising on €5 a day. You cannot start knowing.

A small budget isn't "slow". It's unreadable

A campaign doesn't fail because of a small budget. It fails because a small budget never accumulates enough conversions to tell a good campaign apart from a lucky streak.

At €150 a month with a €30 cost per lead, you get five leads a month. If one month brings three and the next brings seven, did the campaign improve? You don't know. Nobody knows. That entire difference fits inside chance.

With insufficient data, every decision you make is a superstition with a spreadsheet attached.

And what follows is always the same: change the creative, change the audience, pause it, restart it. Each change resets the system's learning, so the next month is unreadable too. You end up paying for twelve months of permanent learning phase.

The number to work out first

Don't start with the budget. Start with your sector's cost per lead or per sale, and multiply by the conversions you need to read the month.

My rule is thirty conversions a month as the minimum for talking about trends, and fifteen to begin sensing anything at all. With the acquisition costs seen in Spain today, that works out like this:

That's the answer to why an online shop can start on €300 and a law firm can't. It isn't that one is smarter: it's that one's lead costs twenty times the other's, and the budget has to cover the arithmetic.

The floor I publish, and why

On the site I put €1,000 a month of ad spend as the floor for management to be worth paying for. That isn't a round number chosen for looks.

Below it, two things happen at once. First, the management fee weighs too much: paying €500 to manage €400 of spend is absurd, and anyone who accepts it ends up — rightly — feeling sold to. Second, the data volume doesn't justify active management: there's nothing to optimise yet, there's only waiting.

When someone tells me they want to start on €300 a month in an expensive-lead sector, the recommendation isn't to hire anyone. It's to save for three months and start with €900, or to put that money somewhere else — the website, the way enquiries are handled, the follow-up on leads they already have — where €300 does move the needle.

Telling someone their budget isn't enough is cheaper for both of us than taking it and explaining three months later why it didn't work.

What to do when the budget doesn't reach

Three routes work better than forcing a small campaign.

Lower the cost per lead instead of raising the budget. A shorter form, a landing page that talks about the problem rather than the company, and a reply in minutes instead of days. That's website and process work, not campaign work, and it's a lot cheaper than buying more traffic.

Start with search rather than discovery. Someone typing "employment lawyer Santa Cruz" already has the problem. They convert far better than someone interrupted in a social feed, so a smaller budget reaches those thirty conversions sooner.

Measure properly before spending. Half the accounts I audit have conversions set up wrong: duplicated, counting thank-you-page views, or firing on every abandoned form. Fixing that costs no ad spend and changes every number that comes after it.

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If you want this worked out on your own figures — your margin, your cost per lead, your conversion rate — write to me and we'll do it on the call. The full reasoning on when a campaign makes or loses money is here, and what I charge to run them is here.

Reference cost ranges: Cactus Marketing, "Cuánto cuesta anunciarse en Meta Ads en España en 2026" and DayByDay Consulting, "Presupuesto mínimo Meta Ads".