This is one of the most common questions growing businesses ask. And the honest answer is: it depends.
Not on some magic formula. It depends on your margins, your growth goals, your cost to get a customer, and how much your customer is worth to you over time.
But there are some clear guidelines that help when putting aside ad spend as percentage of revenue. And there are some common mistakes that cost businesses a lot of money.
There Is No One Right Percentage
Some articles will tell you to spend 5% of revenue on ads. Others say 10%. Others say 20%. They are all right in different situations. And they are all wrong in others.
A business with thin margins cannot afford to spend 20% of revenue on ads. Every dollar they spend needs to come back quickly. A business with high margins and strong repeat customers can afford to spend more up front because each customer is worth much more over time.
A new business in a new market needs to spend more to build awareness. An established business with strong word of mouth might spend less and still grow.
The percentage is not the starting point. The starting point is understanding your numbers.
Start with Your Cost Per Customer
Before deciding how much of your revenue to reinvest, you need to know one number. How much does it cost to get one customer through paid social?
This is called your customer acquisition cost, or CAC. It is your total ad spend divided by the number of new customers that spend produced.
If you spent $2,000 on ads and got 20 new customers, your CAC is $100.
Now compare that to how much one customer is worth to you. If the average customer spends $150 and never comes back, your margin on that $150 needs to cover the $100 CAC plus your product costs. That is tight.
If the average customer spends $150 on the first order and comes back three more times over two years, they are worth $600. A $100 CAC to get a $600 customer is a very good investment.
Understanding your true profitability per customer is the foundation of every smart spending decision.
A Simple Framework by Business Stage
Here is a practical way to think about it based on where your business is.
Early stage (under $500,000 in annual revenue): Most businesses at this stage should spend between 10% and 20% of revenue on paid social. The goal is growth. You are trying to find what works. You need enough spend to test properly and get real data.
Growth stage ($500,000 to $2,000,000 in annual revenue): The range is typically 8% to 15%. You know more about what works. You are optimising. You are scaling what is already proven. You do not need to test as broadly.
Scale stage (above $2,000,000 in annual revenue): This varies widely. Some businesses run at 5%. Others run at 25%. It depends on the margins, the market, and whether the business is prioritising profit now or growth now.
There is no shame in spending more on ads if the return justifies it. And there is no glory in spending less if it means slower growth than you could afford.
The Reinvestment Trap
One mistake many scaling businesses make is reinvesting too little right after a good month.
They have a strong month. Revenue is up. The instinct is to pocket the profit and reduce ad spend. The next month is slower because the ads were cut. Then they increase spend again when things slow down.
This cycle keeps the business from building momentum. Paid social takes time to optimise. The algorithm learns over months, not weeks. The businesses that scale most reliably keep their spend consistent. They increase it gradually when things are working. They do not cut it the moment a target is hit.
Think of ad spend like inventory. You would not empty your shelves when sales are good. You would restock. Consistent ad spend keeps the pipeline full.
The Underspending Trap
The opposite mistake is more common. Spending too little to see real results.
Many business owners set a small budget. $5 or $10 a day. They run it for two weeks. Nothing impressive happens. They conclude paid social does not work for them.
Meta’s algorithm needs a minimum number of conversion events to learn and optimise. At very low budgets, it cannot gather enough data. The campaign never exits the learning phase. Results stay thin and unpredictable.
A budget that is too small is not a safe test. It is an incomplete test. The data you get from it does not tell you whether paid social would work at a proper budget. It only tells you that a very small budget did not work.
If you are going to test paid social seriously, give it enough budget to actually learn.
What a Healthy Reinvestment Ratio Looks Like
A practical way to think about this: for every $1 in CAC (cost to get a customer), you need at least $2 to $3 back in customer lifetime value for the investment to make sense.
If your LTV (lifetime value) to CAC ratio is above 3, you can afford to spend more aggressively. The return justifies the investment. Healthy DTC brands often target a blended MER of 3 to 5, meaning for every dollar spent on all marketing, three to five come back in total revenue.
If your LTV to CAC ratio is below 2, you need to either reduce CAC (make the ads more efficient) or increase LTV (get customers to buy more or come back more often) before scaling spend.
The Bottom Line
There is no universal percentage that works for every business. But there is a logic that works for every business.
Know your cost to get a customer. Know what that customer is worth to you. Know whether the ratio justifies more or less investment. And spend consistently, not in bursts.
Before deciding on your next budget, ask yourself:
- Do you know your current cost per new customer from paid social?
- Do you know how much that customer is worth over their lifetime with your business?
- Is your LTV to CAC ratio above 3?
- Have you been spending consistently, or cutting and increasing based on how last month felt?
- At your current budget, is the algorithm getting enough data to optimise properly?
The right amount to spend is the amount that makes economic sense for your business. Not the amount that feels safe.
Book a free consultation with the SynapseBN team — no pitch, no pressure. Just a straight conversation about what’s working, what isn’t, and what to do about it.
