Time-Decay Attribution
Also known as: Decay-Based Attribution, Time-Weighted Attribution, Position-Weighted Decay Model
A multi-touch attribution model that gives more credit to marketing touchpoints closer in time to the conversion event.
Definition
Time-decay attribution is a multi-touch model that distributes conversion credit across every touchpoint in a buyer's journey, but weights recent interactions more heavily than older ones. The closer a touch is to the purchase or signup, the larger its share of credit. Touches from weeks or months earlier still count, just at a diminishing rate.
Operators use time-decay attribution when sales cycles span weeks and multiple channels influence a deal. It's common in B2B pipelines where a prospect might first see a LinkedIn ad, attend a webinar, read a case study, and then take a sales call — all over 60 days. The model rewards the channels that closed the deal without erasing the awareness work that opened it.
It differs from last-click attribution, which gives 100% credit to the final touch, and from linear attribution, which splits credit evenly. Time-decay sits between them — acknowledging the full journey while still recognizing that recency tends to correlate with influence on the buying decision.
Why It Matters
Time-decay attribution helps your team make smarter budget decisions on channels that close pipeline. If you're running both brand awareness and bottom-funnel retargeting, this model tells you which mix actually drives revenue without starving the upper funnel of credit. That clarity changes how you allocate spend across paid, content, and outbound.
Ignoring time-decay (or defaulting to last-click) usually means killing channels that look weak on paper but are actually doing the heavy awareness lifting. Teams cut their podcast sponsorship or organic content investment, watch pipeline volume collapse a quarter later, and can't figure out why. The reverse problem also happens — over-investing in late-stage retargeting because it gets all the last-click credit.
Examples in Practice
A B2B SaaS company with a 45-day sales cycle uses time-decay attribution to evaluate its demand-gen mix. A prospect saw a paid social ad on day 1, downloaded a whitepaper on day 20, and booked a demo from an email sequence on day 40. The email gets the largest share, the whitepaper a meaningful chunk, and the paid ad a smaller — but non-zero — credit.
A 30-person agency running outbound and inbound in parallel applies time-decay to a six-month deal. Cold outreach started the conversation in month one, a podcast appearance kept the prospect warm in month three, and a referral call closed it in month six. The model surfaces that the referral closed it but the podcast kept the deal alive.
An e-commerce brand with a long consideration cycle for high-ticket items uses time-decay to compare retargeting ROAS against influencer seeding. Last-click made retargeting look like the hero, but time-decay revealed that influencer touches 30-60 days earlier were doing roughly 35% of the work — justifying continued investment in that channel.