Promo codes under-attribute 18-30% versus tracked links

Promo codes under-attribute 18-30% versus tracked links

Discount code ███░░░ | UTM link ████░░ | Both ██████

Codes capture intent-driven buyers who remember to type them. Links catch the silent majority who click and convert without a code.

— Code-only attribution: 0.8-1.6% of exposed audience
— Link-only: 1.1-2.2%
— Deduplicated combined: catches the 18-30% codes miss

The catch: links break on TikTok and Reels where they're not clickable in-frame. There, codes are all you get.

So what: dual-tag every deal; on link-hostile platforms, accept codes will undercount and adjust your model.

Benchmark: n=96 campaigns — median code/link overlap 41%.