“How much should I spend on Google Ads?” is the question I get most from business owners about to start. The honest answer is that it depends, but on things you can calculate.

Working backward

  1. How many sales a month do you want from Google Ads?
  2. Out of ten inquiries, how many do you close? Your close rate.
  3. Out of a hundred ad clicks, how many contact you? Your conversion rate. For local services with a decent landing page, 5–15% is a reasonable starting assumption; real data replaces it fast.
  4. What does a click cost in your category and area? Keyword Planner gives a range.

Monthly budget = sales ÷ close rate ÷ conversion rate × cost per click

An example

A dental practice wants 10 new patients a month.

  • It closes 1 in 3 inquiries: 30 inquiries.
  • It estimates 8 in 100 clicks become inquiries: 375 clicks.
  • Keyword Planner suggests about USD 0.60 per click locally.

375 × 0.60 = USD 225 a month, roughly USD 7.50 a day.

The numbers are illustrative; the point is the formula tells you which lever to pull. If the result is more than you can spend, in order of impact: improve conversion rate (landing page, response speed, clear offer), narrow scope (fewer, more specific keywords in a smaller area), or lower the sales goal for the test phase. What does not work is spending half and expecting half the results: with too few clicks, week-to-week noise swamps any real difference.

The test budget is not the final budget

The first one or two months are for learning which keywords bring inquiries, which hours convert, and what a click really costs. Treat that budget as the cost of answering one question: can Google Ads bring customers at a cost that works for me?

What can you afford per customer?

If a new patient leaves USD 300 of margin, paying USD 22.50 to acquire one is excellent. If they leave USD 20, it is not. Repeat customers change the math; see LTV and CAC together and, for ecommerce, how to calculate ROAS.

How Google charges

Google can spend up to twice your daily budget on a single day, but will not charge more than the average daily budget times 30.4 in a month. A doubled Monday is not a bug.

Billing from Latin America

  • Account currency cannot be changed after the account is created. Switching means a new account and losing history.
  • The real cost is not the platform number. Depending on country and payment method, taxes on foreign services can be added on top, and in Argentina those rules have changed repeatedly. Check with your accountant and budget on the final cost.

In high-inflation markets, review budgets and cost targets quarterly. More in entering LatAm.

Before you spend

For a local business, read Google Ads for local businesses first: one default location setting can take a big share of spend. If you have not decided whether Google is the right first channel, start with small business digital marketing: where to start.