Marketing attribution is how you decide which channel gets credit for a lead or a sale. For a small business the right answer is usually simple: capture the source of every lead in your CRM at first contact, report revenue by original source and by the last touch before the deal, and review both monthly. Fancy multi-touch models come later, if ever.
The common models, in plain terms
- First touch: credit goes to the channel that brought the person in the first time. Good for judging what creates demand.
- Last touch: credit goes to the final interaction before the conversion. Good for judging what closes.
- Linear and time-decay: credit is split across touches. Useful when journeys are long and there is enough data.
- Data-driven (GA4’s default): an algorithm assigns credit. Helpful directionally, but a black box and only for what GA4 can see.
| Model | Credit goes to | Good for | Blind spot |
|---|---|---|---|
| First touch | The first channel that brought them in | Judging awareness channels | Ignores everything that closed the deal |
| Last touch | The final click before converting | Judging closers like branded search | Over-credits search and email |
| Linear | Every touch equally | Showing the whole journey | Treats a banner view like a demo |
| Position-based | 40% first, 40% last, 20% middle | A balanced default for B2B | The weights are arbitrary |
| Data-driven | Whatever the algorithm calculates | Large accounts with volume | A black box that needs lots of data |
| Self-reported | What the customer says | Podcasts, word of mouth, dark social | Memory is imperfect |
Why GA4 alone is not enough
GA4 sees website sessions in a browser. It does not see the phone call, the referral from a past client, the trade show conversation or the deal that closed three months later. Your CRM does. Attribution that the owner can trust lives in the CRM, fed by hidden form fields, call tracking and a required "lead source" field for anything entered by hand.
A setup that works for most small teams
- Capture UTM parameters and the landing page in hidden form fields and store them on the contact.
- Use call tracking numbers by channel for phone-heavy businesses.
- Make original source a required field for every manually created lead.
- Attach revenue to deals, not just contacts, so you can report revenue by source.
- Review monthly: leads, qualified leads, won deals and revenue by original source and by most recent source.
What to ignore
- Attribution debates over small numbers. With 20 deals a month, trends beat models.
- Platform-reported conversions as the source of truth. Every ad platform takes credit for the same sale.
- Vanity metrics such as impressions and followers in a revenue report.
Frequently asked questions
What is the best attribution model?
For most small businesses, first-touch and last-touch reported side by side from the CRM. They answer the two questions you actually have: what brings people in, and what closes them.
Do I need an attribution tool?
Not at first. HubSpot and Salesforce both store original source and can report revenue by it. Tools help once you have high volume and many channels.
Attribution is the first thing we set up in a CRM build-out, because every later decision depends on it.
