Feed posts decay in 48 hours; the half-life problem nobody budgets for

Feed posts decay in 48 hours; the half-life problem nobody budgets for

The question: how long does a B2B social post keep delivering reach, and how does that compare to owned channels like newsletters?

The dataset: decay analyses tracking the share of a post's lifetime impressions delivered over time, across LinkedIn and X, compared with email-open curves.

Three findings:
— Most social posts delivered the bulk of their impressions within ~24–48 hours, then flatlined — a short half-life.
— LinkedIn posts showed a longer tail than X (where the half-life is famously minutes), but still mostly spent within two days.
— Newsletter content, by contrast, reaches a near-fixed list on send and can be re-surfaced, giving owned channels a more predictable, durable curve.

Caveats: decay curves vary with audience size and how long comments keep circulating a post; 'lifetime impressions' is platform-reported and opaque. Treat as directional.

What it means for B2B: social reach is rented and perishable — you re-pay attention costs every cycle. Treating a viral post as a durable asset over-values it. The strategic counterweight is converting rented social attention into owned, durable channels (email, community) you don't have to re-win daily.

Bottom line: social posts are fireworks; build something that stays lit.