Upsell rate = customers who increased their existing spend ÷ eligible customers
More of the same. A different product is cross-sell, and blending the two produces a number that responds to nothing.
Eligibility is the whole denominator question
A customer already on the highest tier with unlimited seats cannot upsell. Counting them dilutes the rate, and the dilution grows as you succeed at moving customers up, so the metric degrades precisely when the motion works.
Recompute eligibility each period against the current packaging. When packaging changes, annotate the series.
Exclude automatic increases
Usage-based pricing produces revenue increases with no sales involvement. A customer whose bill rose because they used more has not been upsold; the pricing model worked.
Both matter, and they are different things:
- Upsell rate: a motion succeeded.
- Usage growth: the pricing model captured expanding value.
Combining them credits the customer success team for the pricing model, and hides whether anyone is actually selling.
Upsell and expansion rate
Expansion rate measures the revenue effect. Upsell rate measures the share of customers involved.
The pair tells you the shape: a low upsell rate with a high expansion rate means a handful of accounts carried the quarter, which is the same concentration risk that shows up in NDR.
A worked example
500 customers. 60 are on the top tier and excluded, leaving 440 eligible. In the quarter, 52 increased seats or tier through a sales conversation, and 38 more saw usage-driven increases with no involvement.
Upsell rate = 52 ÷ 440 = 11.8%
Including the usage increases gives 90 ÷ 440 = 20.5%, which would report the pricing model as a sales achievement.
The traps
- Blending with cross-sell.
- All customers in the denominator rather than eligible ones.
- Counting automatic usage increases.
- Counting contracted annual uplifts, which are indexation.
- Reading the rate without the revenue effect.
Where this sits
Upsell is Measurement in the Tenbound Pipeline Architecture Standard. Its dependency is Market: customers acquired inside the ICP grow into the product, and customers acquired outside it do not, whatever the expansion motion attempts.