Budget and return are two different questions
A budget answers one question: how much am I ready to put in? Return answers another: what came back? People mix them. They set a budget from a feeling and then judge the return by a different feeling. The chain in this guide joins the two with numbers from your own books.
Indian firms add two wrinkles. Many sales to other firms are on credit, so a sale in March may become cash in May. Many sales to consumers are paid on delivery (COD, cash on delivery), and some parcels return when the buyer refuses them (RTO, return to origin). Count sales that were paid for and kept. This is our own reading, and we did not open an official text on it. For direct to consumer (D2C) brands, see our guide on D2C marketing cost and metrics.
The six numbers, in the order they arrive
Numbers arrive at different speeds. Cost per lead shows up in days. Payback and ROI take months. Read the chain from the first number to the last, and trust the later numbers more than the earlier ones.
Cost per lead and cost per qualified lead
A lead is a person who fits your buyer and gave you a way to reach them. A qualified lead can also buy soon. In the example, ₹2,00,000 ÷ 160 gives ₹1,250 for each lead. The same money ÷ 32 gives ₹6,250 for each qualified lead. A campaign can make the first number look cheap while the second stays high. Our lead generation guide explains the difference between an enquiry, a lead and a qualified lead.
Customer acquisition cost
Customer acquisition cost (CAC) is all the money spent to win customers, divided by the new customers who paid. According to Shopify's blog on CAC, published July 2024, the costs to count include advertising fees, software and tools, and marketing staff salaries. The page adds content creation, sales costs that support marketing, and discounts and promotional offers. In the example, all spend is ₹2,00,000 and there are 8 new customers, so CAC is ₹25,000.
Now see what happens if you count only the ad spend. ₹1,25,000 ÷ 8 is ₹15,625. That leaves out the agency fee, the tools and the team's time. The gap between ₹15,625 and ₹25,000 is the gap between a dashboard number and a real one. Our guide on customer acquisition cost in India shows what to count line by line.
Return on ad spend, and the break-even point
Return on ad spend (ROAS) is sales divided by ad spend. According to Google Ads Help, October 2026 (no date on the page), target ROAS is the average conversion value you want for each unit spent on ads. Conversion value can be revenue. Its example is 5 in sales for every 1 spent, written as 500%. Some tools show ROAS as a ratio and some as a percentage. In this guide it is a ratio.
ROAS counts sales. So it can look fine while the firm loses money. In the example, ROAS on ad spend alone is 3.84. On all spend it is 2.4. The break-even ROAS is 1 ÷ gross margin, which is 1 ÷ 0.40 = 2.5. At 2.4 the first orders lose a little, and that matches the loss of 4% in the table. Our guide on ROAS meaning and formula works this out in more detail.
Payback
Payback is the time a cost takes to come back. According to Wikipedia's page on the payback period (last edited October 2026), it is the time needed to recoup the funds spent. The same page lists limits: it ignores cash that arrives after the payback point, and it does not account for risk. Shopify's blog uses the same idea for customers and calls it CAC payback, the time it takes to recoup the cost of acquiring a customer.
In the example, CAC is ₹25,000 and one order brings ₹24,000 of margin. After the first order, ₹1,000 is still to come back. Say the second order arrives about four months after the first. Payback then lands at about month 4. Until then the money is out. So ask how long your cash can wait, because that sets how much a customer may cost.
Return on investment
According to Wikipedia's page on return on investment (last edited October 2026), ROI is the ratio between net income, or profit, and the investment that produced it. The page also says ROI is not adjusted for time. Users choose their own inputs, such as the period or whether overhead is included. An ROI figure shown without its inputs can mislead. So always state the period and the costs you counted.
Our formula is (gross margin from the customers won minus all spend) ÷ all spend. Gross margin is before rent and other overhead, so say so when you report it. In the example, the first orders bring 8 × ₹24,000 = ₹1,92,000 of margin. That is ₹8,000 less than the ₹2,00,000 spent, so ROI is minus ₹8,000 ÷ ₹2,00,000, a loss of 4%. Now say each customer places a second order of the same size within the year. Margin becomes 8 × ₹48,000 = ₹3,84,000. The gain is ₹1,84,000, and ROI is ₹1,84,000 ÷ ₹2,00,000 = 92%. The first month looks like a loss. The year does not. That is why the period matters.
How to set a marketing budget: three methods, no borrowed benchmarks
You will see rules that say spend a fixed percent of revenue. We do not quote one. We did not open an official or public page that gives such a percentage with a date. A figure from another industry or another country may not fit your margin. Use one of the three methods below, and use a second one as a check.
Method 1: what you can afford to lose while you learn
Start with a limit and not a target. Ask how much the firm can lose over the next three months without hurting salaries, stock or loans. Say a firm decides it can lose ₹6,00,000 in a quarter. It spends ₹2,00,000 a month for three months. It agrees to stop or change the plan if cost per qualified lead stays above what its margin allows.
Why three months? According to Google Ads Help, October 2026 (no date on the page), you should report conversion values for four weeks, or one to two conversion cycles, whichever is longer, before you set a target ROAS. Buyers who take two months to decide need at least that long. That reading is ours. The method suits a first test, a new product or a new city. It says what you can survive, and not what the right figure is.
Method 2: from the margin of a customer and the customers you want
Say the same firm wants 20 new customers a month. A customer brings ₹48,000 of gross margin in the first year, from two orders of ₹24,000. The owner chooses to spend at most half of that to win a customer. Half is the owner's choice and not a rule. The highest CAC is then ₹24,000. The budget is 20 × ₹24,000 = ₹4,80,000 a month.
Now check the chain backwards. Say one in four qualified leads becomes a customer. Then 20 customers need 80 qualified leads. Each qualified lead can cost at most ₹24,000 ÷ 4 = ₹6,000. If the market gives qualified leads at ₹9,000 each, a customer costs ₹36,000, which is above the ₹24,000 limit. The plan then needs a better margin, a better close rate or fewer customers. You learn this before you spend, which is the use of the method.
Method 3: from last year's results
Say last year the firm spent ₹18,00,000 and won 60 customers. CAC was ₹18,00,000 ÷ 60 = ₹30,000. It wants 75 customers this year. At the same CAC the budget is 75 × ₹30,000 = ₹22,50,000. A cost can rise as spend rises, because the easiest buyers are reached first. It does not always happen, so watch it each month. Plan a range. If CAC rises by 10% to ₹33,000 (an assumption, made up), 75 customers cost ₹24,75,000. Check both figures against method 2. Is ₹33,000 still below what a customer's margin allows? The method needs honest records of cost and of new customers. If last year's books were messy, the plan repeats the mess. A new firm can begin with method 1 and move to method 2 as data comes in. An older firm can use method 3 and check it with method 2. Write down the budget, the loss limit and the review date. To split the total across channels, read our guide on how to split a marketing budget.
What to avoid when you fix the number
- Copying a percent from an article, a competitor or another country.
- One yearly figure that nobody reviews. Release the money in parts, and review each part.
- Counting only ad spend. Agency fees, tools, content, discounts and team time are part of the cost.
- Judging by sales when margins are thin. Judge by gross margin.
- Cutting the budget in a slow month before you check payback. The cost may be about to come back.
- Giving sales no clear time to reply. A lead nobody calls within a day or two is money gone.
- Forgetting how ad accounts spend. According to Google Ads Help, October 2026 (no date on the page), a campaign might spend up to twice its average daily budget on a given day. By the end of the month it will have spent no more than 30.4 times the average daily budget. So a daily budget of ₹4,000 can reach ₹8,000 on one day, and the month stays at or below ₹1,21,600.
If you also need to know what media and agencies charge, start from our cost guides. They cover prices. This guide covers how to decide and measure.
Why your ad dashboard and your own sheet will not match
Two reports of the same month can show different numbers, and both can be correct. There are three common reasons.
- You choose what counts. According to Google Ads Help, October 2026 (no date on the page), you choose what to identify as valuable, such as a purchase, a sign-up or a phone call. A cost per conversion is not CAC unless the conversion you set is a paying customer.
- Credit is shared in different ways. According to Google Analytics Help (no date on the page), paid and organic last click ignores direct traffic. It gives 100% of the value to the last channel the customer clicked through. Data-driven attribution spreads credit using data for each key event. The model you pick changes which channel looks good.
- Time runs out. According to Google Ads Help, October 2026 (no date on the page), the default window for clicks is 30 days, and a conversion after the window is not recorded. A buyer who takes 90 days to sign will not show up in the ad account at all.
So keep one sheet that you own: leads, qualified leads, new customers, cash received and returns. Use the ad account to steer, and the sheet to judge. Setting up tracking so that every lead and sale carries its source is the work of our analytics and tracking service.
A monthly review that takes about an hour
A budget is useful only if someone looks at it. Fill this table each month from your books, not from the ad account. The first row is our example and is made up.
| Month | All spend | Ad spend | Leads | Qualified leads | New customers | CAC | ROI so far |
|---|---|---|---|---|---|---|---|
| Say month 1 | ₹2,00,000 | ₹1,25,000 | 160 | 32 | 8 | ₹25,000 | A loss of 4% |
Add cash received and returns as two more columns if you sell on credit or on delivery. ROI so far is the margin earned to date from that month's customers, set against that month's spend. It rises as repeat orders arrive. The steps below show the order of the review.
Questions to ask an agency or your finance head
For an agency
- Which number will you report as the result: leads, qualified leads, customers or sales? How do you define each one?
- What is inside the cost you show me: ad spend, your fee, tools, content?
- Which conversions are set in the ad account, and does each one match something I would pay for?
- How will you count sales that come by phone, by WhatsApp or after the tracking window ends?
- If cost per qualified lead stays above my limit for two months, what will you stop or change?
- Can I see the ad accounts and the tracking myself, at any time?
For your finance head
- What gross margin should we use for each product, and does it include freight and returns?
- Which costs go into CAC? Do we share a part of salaries and tools?
- How long can our cash wait before the money must come back? That sets the payback limit.
- Do we count sales when billed or when cash arrives, and how do returns and credit notes enter?
- Who signs the monthly sheet, and on which day of the month?
If you want to see how we think about measuring return from ads, read our page on performance marketing.
Reading order
Start here if you are new, and jump to the one you need if you are not. Two more guides in this set are coming: one on marketing ROI and one on cost per lead. They are not published yet, so they are not linked here.
The two number guides
- ROAS meaning, formula and a worked example: sales per rupee of ads, and the break-even point.
- Customer acquisition cost in India: the formula, what to count and payback.
Short definitions
- CAC: the cost of winning one paying customer.
- ROAS: sales for each rupee of ad spend.
- CPL: the cost of one lead.
- LTV: what one customer brings over all their orders.
Setting the budget
- Marketing budget split in India: how to share a budget across channels.
- Trade show marketing return: what a stall brings back.
Leads
- Lead generation in India: meaning, methods and services.
- B2B lead generation in India: for business to business (B2B) firms that sell to other firms.
Direct to consumer
- D2C marketing cost and metrics in India: numbers for online brands.
What things cost
- Cost guides: the hub for what media and agencies charge.
- Digital marketing cost in India.
- SEO cost in India: search engine optimisation (SEO) fees.
- Google Ads management fees in India.
- CPM calculator: a tool for cost per thousand views (CPM).
Services
- Performance marketing: ads judged on leads and sales.
- Analytics and tracking: so that every lead carries its source.












































