“How much do I need to spend on ads?” is one of the first questions every small business asks. And while there’s no magic number that works for everyone, there is a clear, orderly way to figure it out. Instead of picking a number out of thin air, you work out the budget backwards: starting from the clients you need.
Working it out backwards
You need three numbers:
- How many new clients you want each month.
- How many leads it takes you to close one sale. If 2 out of every 10 people who message you end up buying, your close rate is 20%.
- How much each lead costs you in ads. You get this number during the testing phase.
With that, the formula is simple:
Monthly budget = clients you want ÷ close rate × cost per lead
An illustrative example (the numbers are made up, just to show the math): if you want 10 clients a month, you close 2 out of every 10 leads, and each lead costs you $3 USD, you need 50 leads. 50 leads × $3 USD = $150 USD a month.
Your real cost per lead varies a lot depending on your industry, your city, your offer and the quality of your ads. That’s why the first step is always to measure it.
The testing phase
Before you spend big, it pays to run a testing phase of a few weeks on a small budget. The goal isn’t to sell a lot, it’s to learn:
- Which audience responds best.
- Which message and which creative bring in the most leads.
- How much, in your case, each person who messages you costs.
- How qualified those leads are.
After the test, you’re no longer guessing: you know what a lead costs you and can work out how much to spend to hit your goal.
What makes every dollar go further
A good creative
On Facebook and Instagram, the video or image decides whether someone stops or keeps scrolling. A creative that stops the scroll lowers the cost of every lead.
Video creatives made for ads.
The right audience
An audience that’s too broad spends money on people who would never buy from you; one that’s too narrow burns out fast. Testing helps you find the middle ground.
Replying fast
If the ad works but you take hours to reply, that lead goes cold and the money is wasted. Instant replies and follow-up are part of how well your ads perform; here I explain how to follow up with leads on WhatsApp.
Consistency
Turning your ads on and off every week doesn’t give campaigns a chance to learn. A moderate, steady budget beats a big, on-and-off one.
Mistakes that make your ads more expensive
- Using the “Boost” button instead of Ads Manager.
- Measuring likes instead of leads.
- Changing everything every couple of days without giving the campaign time.
- Sending people somewhere confusing, with no clear reply and no next step.
- Not knowing what a client is worth to your business. If you don’t know how much a sale brings in, you don’t know how much you can pay to get it.
What else you should know
- The ad budget is paid directly to Meta. That way you know exactly how much is being spent.
- Your ad accounts should be yours. Your campaign history and data belong to your business.
- Managing the ads is separate from the ad budget. What you pay the platform is one thing; the strategy, creative and optimization work is another.
If you’re still torn between platforms, I explain whether Meta Ads or Google Ads is right for you.
How I can help
I manage Meta, Google and TikTok campaigns for small businesses across Mexico, online: I design the testing phase, produce or edit the creatives, measure the real cost of each lead and scale only what works. You get clear reports, no jargon.
If you want to know how much it makes sense to spend to reach your goal, message me and we’ll run the numbers with your business’s data.