How to Track Offline Advertising: QR Codes, Vanity URLs and Promo Codes

By Utkarsh Jaiswal · September 25, 2026 · 2 min read

Measure car wraps, billboards and stickers with vanity URLs, UTM redirects, promo codes, a branded-search baseline and a 'how did you hear' field.

The usual objection to offline advertising is "you can't measure it". You can't measure it the way you measure a Google ad, but you can measure it well enough to know whether it's working. Here's a setup that takes an afternoon.

1. Give every offline ad its own door

Vanity URLs

A short, memorable path that only appears on that one ad, like yourbrand.com/car. Redirect it to your homepage with UTM parameters so your analytics sees it as a separate source:

yourbrand.com/car → yourbrand.com/?utm_source=harrier&utm_medium=vehicle&utm_campaign=hood

People who type it in have almost certainly seen the ad.

QR codes

Useful on things people stand next to, such as posters, packaging and parked cars. Much less useful on things moving past them. Point the QR code at a UTM-tagged URL too, and make it big.

Promo codes

A code that only exists on the ad, like HOOD10. It catches buyers who arrive through search or word of mouth after seeing it.

2. Set a branded-search baseline

Before the ad runs, note how many people search for your brand name each week. Google Search Console shows this for free. A physical ad that works usually shows up first as a rise in people searching your name, not as clicks.

3. Ask people

Add an optional "How did you hear about us?" field at signup or checkout, with a free-text answer. It's crude, and it often catches what the other methods miss.

4. Collect evidence the ad actually ran

Attribution is pointless if the ad wasn't out there. Ask for dated photos or video. On the Harrier.ev, dated driving video is published throughout the six months, so you can line up your traffic against the days the car was out.

5. Read the results honestly

Vanity URL visits are your lower bound: definitely from the ad.
The branded search lift is your likely range.
Survey answers fill in the story.

Put those together and you have a defensible estimate of what the ad did. It won't be exact, and it doesn't need to be.

A setup for a Harrier.ev placement

Put a vanity URL in your artwork, short enough to read from the next lane.
Use a promo code that matches the placement name.
Record your branded-search baseline in Search Console the week before printing.

Then the six months of driving have a scoreboard. See the placements.