1-click post-purchase upsell: 16.64% take rate
Test run byDave DiederenSyntra Labs
Commentary byLiftArchiveOur analysis, not theirsAdding a 1-click complementary upsell after checkout got 16.64% of buyers to accept the offer, worth $16.50 per acceptance. Dave Diederen ran this for a client, and they credit the result to choosing a product that fits the first purchase. There was no control group, so this is an offer performance number, not a split-test lift.
- Offer acceptance rate: 16.64% of buyers who saw the offer took it.
- Value: $16.50 of extra revenue per accepted offer.
- Daily acceptance swung widely after launch, from under 10% to above 30% on single days.
- No effect on the main conversion rate was reported, since the offer only appears after the first order is placed.
The change
A one-product, 1-click offer appears right after payment.
Simplified mockup drawn by LiftArchive from the shared screenshots.
Control
Before the change, buyers saw the standard thank-you page with no post-purchase offer.
Variant
After paying, buyers were offered one complementary product they could add with a single click, without re-entering payment details.
Why it likely won
Our reading of the result, not the practitioner's claim.
- the offer worked because it was a natural next step, such as a moisturiser after a serum.
- one click removes the effort of a second checkout, so buyers decide on impulse while they're still in buying mode.
- a single product keeps the choice simple, with nothing to compare.
Caveats: This is a before/after view of a new offer, not a split test against a control. The offer started around February 10, 2026, and the number of buyers, the products and the discount were not shared.
Who ran it
Dave Diederen (@DaveDiederen) shared this test on X. The numbers and screenshots are theirs.
View the original post on X
How to run this test on your store
- Hypothesis
- If we offer one complementary product with 1-click checkout after purchase, then revenue per order will rise because buyers add a natural partner item while still in buying mode.
- Primary metric
- Revenue per order (including accepted upsells)
- Guardrails
- Refund rate on upsell items
- Margin per order
- Repeat purchase rate
- Who should test it
- Stores with clear product pairings, like skincare routines or outfit pieces. It fits less well for single-product stores with nothing that naturally goes with the main item.
Questions
What is a good post-purchase upsell conversion rate?
This offer was accepted by 16.64% of buyers. Results depend heavily on how well the product fits the first purchase.
What should I offer in a post-purchase upsell?
Offer one product that goes with what the buyer just bought, such as a moisturiser after a serum or trousers after a shirt.
Does a post-purchase upsell hurt checkout conversion?
It appears only after the order is placed, so it shouldn't affect the first purchase. This test didn't report a check on that.
@joshtCRO