How much should you spend on ads? Work it out from one customer

"How much should I spend on Google or Facebook ads?" is one of the questions we hear most often from local business owners. It is also the wrong first question. Pick a number out of the air, ₹5,000 or ₹20,000 a month, and you have no way of knowing whether it is too little to learn anything or more than the business can safely lose.

The right first question is: how much can I afford to pay for one new customer? Once you know that, the budget follows from simple arithmetic, and you have a clear way to judge whether ads are working. This article walks through the method step by step. Every figure in it is an example to show the calculation; use your own numbers for your business.

Ad budget and agency fees are two different things

Before the arithmetic, one point that confuses many owners. When you advertise on Google or Meta (Facebook and Instagram), there are usually two separate costs:

• The ad budget, which you pay to Google or Meta for showing your ads and receiving clicks.
• The management fee, if you hire someone to plan, set up and optimise the ads.

Always know which is which. In all our growth plans, the ad budget is not included: you pay Google or Meta directly, from your own account, so you can see exactly where every rupee goes. Our fee covers the work of running the campaigns, and the Google and Meta ads management is part of our Pro and Max plans.

Step 1: work out what one customer is worth

Start with profit, not price. If you sell a ₹1,000 service and ₹600 of that covers materials, staff and rent, the profit from one sale is about ₹400. Then think about how often a customer comes back.

• A salon client who visits six times a year and leaves ₹500 profit each visit is worth about ₹3,000 in a year.
• A café customer who comes twice a month and leaves ₹60 profit each time is worth about ₹1,440 a year.
• A one-time customer, say for a wedding service, is worth the profit from that single job.

This figure is often called customer value or lifetime value. You don't need it to be exact; a reasonable estimate is enough to make much better decisions than guessing. Our pays-for-itself calculator lets you try different values for your industry in a few seconds.

Step 2: decide the most you will pay to win one customer

Now choose a limit: the most you are willing to pay in ads to win one new customer and still be happy. Many owners start with a third of the customer's value or less, which leaves room for mistakes while campaigns are learning and for the other costs of serving the customer.

In the salon example, a third of ₹3,000 is ₹1,000. So the salon decides: we will pay up to ₹1,000 in ads for each new client. This is your target cost per customer.

Step 3: work back to what you can pay per enquiry

Ads don't produce customers directly; they produce enquiries, some of which become customers. So you need to know roughly what share of enquiries buy. If, from experience, one in four enquiries becomes a client, your close rate is 25%.

Affordable cost per lead = target cost per customer × close rate. In our example: ₹1,000 × 25% = ₹250 per enquiry.

Now you have a number to judge any campaign against. If an ad brings enquiries at ₹180 each, it is comfortably within your limit. At ₹400 each, it is too expensive unless your close rate improves. Our article on the five numbers that show whether your website makes money explains close rate and cost per lead in more detail.

Step 4: set a starting budget that can actually teach you something

A campaign needs enough enquiries before you can judge it fairly. Two enquiries prove nothing either way. A reasonable first test is around twenty enquiries.

Test budget = target cost per lead × number of enquiries you want. Twenty enquiries at ₹250 means a test budget of about ₹5,000. Spread it over two to four weeks, so the campaign has time to learn which people respond.

During the test, change as little as possible. Constant changes reset the learning and make it hard to know what worked.

Step 5: check the real numbers against your limits

At the end of the test, calculate the real figures:

• Real cost per lead = ad spend ÷ enquiries.
• Real close rate = new customers ÷ enquiries.
• Real cost per customer = ad spend ÷ new customers.

To count enquiries properly, track all of them: form enquiries, WhatsApp taps and call taps from the ad's landing page. If you only count forms, you may think the ads are failing when people are simply calling you. Our monthly results report counts all three for this reason.

Step 6: scale only what works

• Cost per customer below your limit → increase the budget gradually, by about a fifth at a time, and keep checking. Sudden big increases can raise costs while the campaign adjusts.
• Above the limit, but close → before spending more, improve the two things you control: the landing page (to raise conversion) and your follow-up (to raise close rate). Our guide to what belongs above the fold covers the page; replying within the first hour often fixes the rest.
• Far above the limit → stop, and change something bigger: the offer, the audience, the area, or the channel.

Where should the money go first?

For most local businesses, the order that wastes the least money is:

1. Free foundations first: a complete Google Business Profile and a website that converts. Ads sent to a weak page waste money. See our Google Business Profile guide and local SEO checklist.
2. Search ads next, for people already looking for your service. They usually cost more per click but bring people who are ready to buy.
3. Social ads after that, to reach people nearby before they search: good for offers, new openings and festivals, but the leads often need more follow-up.

The whole method on one page

Putting the salon example together: a client is worth about ₹3,000 a year, so the salon will pay up to ₹1,000 to win one. One in four enquiries books, so each enquiry can cost up to ₹250. A first test of twenty enquiries needs about ₹5,000 of ad budget. If the test brings twenty enquiries for ₹4,600 and six become clients, the real cost per client is about ₹767, comfortably under the ₹1,000 limit, and the salon can raise the budget step by step. If it brings only two clients, the cost is ₹2,300 each, and the page or the follow-up needs work before more money goes in. (All figures illustrative.)

Common mistakes

• Judging on clicks or likes. Clicks are a cost, not a result. Judge on enquiries and customers.
• Sending ads to the home page. Send each ad to a page that matches it.
• Stopping too early. Give each test enough enquiries to judge fairly.
• Forgetting the follow-up. The cheapest way to lower cost per customer is often to close more of the enquiries you already get.

Get help working out your numbers

If you would like this worked out for your own business, our Digital Growth plans include ads management with the arithmetic done for you every month: cost per enquiry, close rate and cost per customer. The ad budget always stays yours, paid directly to Google or Meta. Not ready for ads yet? Start with the foundations: see your new website with a free first draft, or get a free growth check of the one you have. Questions? contact us.