How much a small business should spend on Google Ads per month

Start from enquiries, not from the budget

The question isn’t “how much can I spend”, it’s “how many new enquiries a month do I want”. The budget follows from that.

The formula

Budget = enquiries you want ÷ share of clicks that become an enquiry × cost per click

Example (made-up numbers, just to show the maths): you want 10 enquiries a month. If one in twenty clicks becomes an enquiry (5%), you need 200 clicks. If a click in your field costs €0.80, that’s €160 a month.

Where the numbers come from

• Cost per click: Google Ads has a free Keyword Planner that shows an estimated cost per click for your terms and area.
• Share of clicks that become an enquiry: you don’t know it at first. That’s what the first month is for, with call and form tracking switched on.

How long to test

Long enough to collect at least a few dozen clicks per service. With too few clicks, every conclusion is chance. For most small businesses that means at least a month on one or two services.

When to raise the budget

When you know what one enquiry costs you and what one job is worth. If an enquiry costs you €15 and an average job brings €300, you have a clear reason to spend more. If you don’t know those numbers, raising the budget is guesswork.