How much should you spend on Facebook ads? Do the arithmetic first

Every answer to this question is either “it depends” or a number someone made up. It does depend, but on four things you already know or can look up in ten minutes, and once you have them the budget is arithmetic rather than opinion.

Work backwards from the revenue you need

The calculation runs in one direction only: from the result you want to the money it takes to get it.

1. The revenue or number of customers you want per month.
2. Average order value, or average deal value.
3. Your conversion rate, from click to order, or from lead to customer.
4. Your cost per click, from the last 30 days of your own data.

Target revenue divided by order value gives the orders you need. Orders divided by conversion rate gives the clicks you need. Clicks multiplied by cost per click gives the budget. Then divide the revenue target by that budget: the number you get is the ROAS your plan quietly assumes, and that is where most plans fall apart.

Do not use benchmark figures for steps three and four if you have any traffic at all. Your own conversion rate is in GA4 or Shopify reports. Your own cost per click is in Ads Manager. Industry averages are for people with no data, and you probably have some.

Worked example: an e-commerce store

A store wants $50,000 a month in revenue from Meta ads. Average order value is $80 and the site converts paid traffic at 2%.

A 1.8 ROAS on a 40% gross margin loses money on every order. So the plan does not work, and you learned that before spending anything.

Now look at which input moves it. Lifting the conversion rate from 2% to 3% cuts the clicks needed to 20,833 and the budget to $18,750, which is a 2.7 ROAS. Raising average order value to $95 with a bundle has a similar effect. Cutting cost per click by 20% with better creative helps too. Doing all three turns an unprofitable plan into a workable one, and only one of the three is a media buying task. That is why we will often argue for fixing the page before raising the budget when a store asks us to scale.

Worked example: a lead-generation business

A service business wants 10 new clients a month. Average deal value is $3,000. The sales team closes 20% of qualified leads, and about 60% of enquiries are qualified.

$290 to win a $3,000 client is a good trade, so this plan is fundable. Notice which numbers you had to take from the CRM rather than the ad account. If you do not know your close rate or what share of enquiries are worth calling, you cannot size a lead-generation budget, and you will end up judging the campaign on cost per lead alone. That is the fastest route to a rising cost per lead and falling sales.

The learning phase puts a floor under the budget

Meta’s own documentation describes an ad set leaving the learning phase at around 50 optimisation events in a rolling week. Below that, delivery stays unstable and the results you see are mostly noise.

Turn that into money. If your cost per lead is $35, 50 leads a week costs $1,750, which is about $7,500 a month per ad set. Most small businesses cannot fund that, and they should not pretend otherwise. The practical responses are:

• Run one ad set, not five. Splitting $3,000 across five ad sets guarantees that none of them learns.
• Optimise for an event that happens more often, such as a lead rather than a qualified consultation, and watch quality separately.
• Use campaign budget optimisation so the budget concentrates where conversions actually happen.
• Accept that you will make decisions on two weeks of data rather than one.

The same logic applies on Google. Thin budgets spread across many campaigns produce accounts full of campaigns that each have too little data to be judged, which is also how Google Ads budgets end up wasted.

Why under $1,000 a month rarely works

$1,000 a month is roughly $33 a day. At a $30 cost per result that is one conversion a day, seven a week, against the 50 the system wants. It can work, slowly, with one ad set and patient creative testing. Below that it generally cannot: at $500 a month you are buying four conversions a week, which is not enough to tell a good ad from a bad one.

That is why $1,000 a month, or PKR 250,000, is the minimum ad budget we recommend. It is not a sales floor. It is the point below which we would be charging you to manage a campaign that cannot gather enough data to improve.

What to spend it on instead until you can fund ads

If your budget is under that floor, there are three things that make every future dollar of ad spend go further, and all of them are one-off costs rather than monthly ones.

1. Tracking. Conversion events that fire once, with values, server-side where it matters. Without this you cannot measure anything you spend later.
2. One landing page built for one offer. Lifting conversion rate from 1.5% to 3% halves your cost per sale permanently. No bid strategy does that.
3. Follow-up speed. If enquiries wait hours for a reply, you are losing leads you already paid for. Automating the first response is cheap, and speed to lead is usually the biggest single improvement available to a small lead-gen business.

Spend two months on those three, then start advertising with a budget that can actually learn. You will get to profitability faster than if you had run thin ads for six months.

What this looks like when we do it

A women’s apparel brand came to us spending $3,000 a day with a cost per conversion 42% above target. We fixed tracking first, rebuilt the funnel, tested new creative weekly and then raised daily budgets in 20% steps with automated rules protecting ROAS. Spend reached $26,849 a day at a 389% blended ROAS over six months, detailed in the women’s apparel ads case study. Scaling was the last step, not the first, and the step size mattered as much as the direction.

Where that leaves you

Run both calculations on your own numbers tonight. If the required ROAS looks achievable and the budget is above $1,000 a month, you have a plan worth funding. If the arithmetic fails, you now know which input to fix first, and it is usually conversion rate or offer rather than budget.

If you want a second opinion on the numbers before you commit, our free audit includes a strategist reviewing your accounts first, or read how we structure paid media once a budget is set.