How to Calculate Your Marketing ROI

30 June 2026·4 min read

Quick answer: Marketing ROI is worked out as (revenue generated by a channel or campaign − what it cost to run) ÷ what it cost to run, usually expressed as a percentage. To use it properly you need two things most businesses skip: a clear cost for each channel, and a reliable way to attribute revenue back to it — through UTM links, unique phone numbers, discount codes, or simply asking new clients how they found you. Without attribution, ROI is a guess dressed up as a number. 📈

Every business owner asks whether their marketing is actually working at some point — ROI is how you answer that with a number instead of a feeling. It's a simple formula, but the businesses that get real value from it are the ones who set up tracking before they need the answer, not after. 💖

Where marketing ROI calculations go wrong

Skipping attribution entirely — calculating ROI off total revenue instead of the revenue you can actually trace back to a specific channel or campaign.
Forgetting hidden costs — counting ad spend but not the time spent managing the campaign, design costs, or the software subscription that made it possible.
Judging too early — measuring the ROI of an SEO or content strategy after six weeks, when it realistically needs months to show its return.
Comparing channels on raw ROI alone — a channel with 150% ROI on $200 spent isn't automatically better than one with 80% ROI on $5,000 spent; scale matters as much as percentage.
Never revisiting the number — calculating ROI once, then running the same channel unchanged for a year without checking whether it's still true.

The copy-paste ROI worksheet — fill this in for each channel or campaign:

Channel/campaign: ___________
Total cost (ad spend + tools + your time at a fair hourly rate + any design or production cost): $___________
Revenue directly attributable to this channel (from UTM links, a unique phone number, a discount code, or asking how they heard about you): $___________
ROI = (Revenue − Cost) ÷ Cost × 100 = ___________%

Worked example: spent $600 (including 4 hours of your own time at $50/hr), attributed $2,100 in booked revenue → ($2,100 − $600) ÷ $600 × 100 = 250% ROI.

Repeat this for every channel every quarter, and rank them against each other — not against an arbitrary good number pulled from the internet.

Here's what that discipline actually uncovers in practice. 🌴

Financial planner: A practice ran LinkedIn content for a year assuming it wasn't doing much because it generated no direct enquiries. When they started asking new clients how they'd heard of the practice and cross-checking against who'd engaged with LinkedIn content first, they found it was quietly influencing over a third of new signed clients — the ROI was real, it just wasn't showing up where they were looking.

Real estate agent: An agent tracked the cost of a print letterbox drop against boosted Instagram posts for the same suburb over a quarter, using a dedicated phone number for each. The letterbox drop had a lower cost per enquiry but far fewer of them, while Instagram cost more per lead but brought triple the volume — proof that better ROI and the better channel to invest more in aren't always the same answer.

Law firm: A firm calculated the ROI of sponsoring a local business awards night by asking every new client at intake how they'd heard about the firm for the following six months, not just the month after the event. Several clients mentioned the sponsorship months later — a reminder that some channels have a long tail attribution won't catch if you stop measuring too soon.

The honest nuance

Marketing ROI is never perfectly accurate — some influence, like a conversation at a networking event, or a friend's recommendation prompted by an ad they saw three months earlier, will always slip through the cracks of any tracking system. The goal isn't a perfect number; it's a good-enough number, tracked consistently, that lets you compare this channel to that one and make better decisions than gut feel alone.

💡 Heads up: always include your own time in the cost side of the formula. A channel that looks free because it only costs hours can quietly be your most expensive one once you account for what those hours are actually worth.

Frequently asked questions

What counts as a good marketing ROI?

There's no universal number — it varies hugely by industry, channel and how you count costs. Rather than chasing a benchmark, compare your own channels against each other and aim to improve your own numbers over time.

How do I calculate ROI if I can't track exact attribution?

Use the closest proxy you have — asking how they heard about you at every enquiry, unique phone numbers per channel, or dedicated landing pages. Imperfect attribution beats no attribution, and it gets more accurate the more consistently you ask.

Should I calculate ROI for every single channel?

Start with your two or three biggest spends — that's where inaccurate ROI does the most damage to your budget decisions. Smaller, low-cost channels can be reviewed less rigorously until they start taking up a meaningful share of spend.

How often should I recalculate marketing ROI?

At least quarterly, and always before making a decision to increase or cut a channel's budget. Costs, conversion rates and attribution accuracy all shift over time, so a number from a year ago may no longer reflect reality.