The average NDR isn't a rejection — it's two calendars failing to meet. The courier arrives Tuesday noon on a route optimised for the depot; the buyer is at the office until seven. The parcel goes back marked "customer unavailable", the buyer finds out Thursday, and the return clock is already running. Letting the buyer pick the day dissolves most of this instantly.

Why slots work where calls don't

A re-attempt window moves the fix from courier-time to buyer-time. The buyer taps a link, sees two or three real options — tomorrow, day after, weekend — and picks one. That response converts the NDR from an undirected retry into a scheduled appointment, which is the difference between "attempted again" and "delivered second attempt".

The psychology matters too: a buyer who chose the day has committed. Doorstep refusal on a self-scheduled delivery is rare — refusal concentrates on surprise deliveries.

~40–60%
Share of NDRs that are timing failures a slot resolves
hours
How fast buyers respond when offered a choice — versus days of phone tag

Rules for offering windows

Only real days. Don't offer Saturday if the carrier doesn't deliver there Saturdays — a promised slot that misses is worse than no slot. Pull the carrier's actual attempt window for that PIN. Two or three options max. A calendar of every weekday is decision paralysis, not convenience. Deadline the choice. "Pick by tonight" matches the courier's retry cadence — an open-ended picker lets the RTO window close while the buyer deliberates.

A delivery slot isn't a feature for the buyer's convenience. It's the courier's second attempt, aimed.

Pure Parcel's buyer link lets the customer reschedule to a day that works — the response writes back to the carrier as a re-attempt instruction.

See how →

The bottom line

"Customer unavailable" almost always means "unavailable at the time you chose". Offer the choice and watch the NDR rate fall — the parcels deliver on the second attempt because the second attempt finally has a date.

Ship every courier without leaving your store

Pure Parcel is the multi-courier layer for Indian stores — hyperlocal and national carriers in one booking flow.

Porter, Borzo & national carriers, on the order page
Live rate comparison on every order
Your own courier accounts or ours — your rates apply
Carrier rate & platform fee shown as separate lines
COD collection & tracking built in
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