Co-terming
Also called: Co-term, Coterming, Coterminous, Co-termination, Aligned renewal
To co-term means aligning add-ons and subscriptions to one shared end date so they renew together. Coterming explained with a diagram and worked example.
Co-termed add-on charge = Full period price × (Days until shared end date ÷ Days in period)
To co-term means to align a new subscription or add-on to the end date of the customer’s existing contract, so everything renews together on one date. The add-on is charged only for the time left until that shared date — a prorated first term — and then renews at full price with the rest of the account.
When a customer buys an add-on eight months into a twelve-month contract, you have two choices. Give the add-on its own twelve-month term — leaving the account with two renewal dates — or co-term it: charge four months’ worth now and align it to the existing end date. Coterming is almost always the right answer for anything beyond a handful of accounts.
Coterming in one picture
Worked example
A customer signs a 12-month contract on January 1 for 100 seats at $120 per seat per year. They expand twice:
| Change | Date | Co-termed charge | Renews at |
|---|---|---|---|
| Base: 100 seats | Jan 1 | $12,000.00 | $12,000 |
| +20 seats | May 1 (245 days left) | 20 × $120 × 245 ÷ 365 = $1,610.96 | $2,400 |
| Analytics add-on, $6,000/yr | Sep 1 (122 days left) | $6,000 × 122 ÷ 365 = $2,005.48 | $6,000 |
| Renewal quote | Jan 1, next year | $20,400 |
Without coterming, the same customer would have three renewal dates — January, May and September — and three separate conversations about price.
Why it is worth the proration
Without co-terming, a customer who has expanded four times has five renewal dates. That means five renewal conversations a year, five invoices to reconcile, five chances for one line to lapse unnoticed, and no single moment at which the whole relationship is reviewed.
With co-terming there is one date, one renewal quote covering everything, and one negotiation — which is where price uplifts and expansion get agreed. It is the foundation of Bunny renewal management.
What it requires
The mechanics are straightforward proration — but they have to be applied to the initial partial period only, with the add-on then falling into the shared renewal cycle at full price. Systems that can only prorate mid-period changes to an existing charge, rather than align a new charge to an existing end date, force this to be done by hand.
The renewal quote then has to reassemble the whole account: base subscription, every add-on, current quantities, whatever discounts and uplifts apply. That is only straightforward when all of it lives on one subscription record rather than being spread across separate contracts that happen to share a customer name.
Co-terming in Bunny
Add-ons and upgrades quoted mid-term in Bunny are co-termed with the existing subscription by default: prorated to the shared end date, billed on the same invoices and included in a single renewal quote when the term ends.
Frequently asked questions
What does co-term mean?
To co-term means to give a new subscription or add-on the same end date as the customer’s existing contract, so everything renews together. The add-on is charged only for the time left until that shared date.
Is it co-term, coterm or co-terminous?
All three are used. “Co-term” and “coterm” are the verb, “coterming” or “co-terming” is the practice, and “coterminous” describes contracts that end on the same date.
How do you calculate a co-termed price?
Multiply the add-on’s annual price by the days remaining until the shared end date, divided by the days in the year. A $6,000/year add-on bought with 122 days left costs $6,000 × 122 ÷ 365 = $2,005.48 for the first partial term.
Why co-term subscriptions?
One renewal date means one renewal quote, one negotiation and one invoice schedule. Without coterming, a customer who expands four times has five renewal dates and five chances for something to lapse.
When should you not co-term?
When the time left is very short. An add-on bought two weeks before renewal is often better quoted on the renewal itself, or co-termed to the following term end, so the customer isn’t invoiced twice in a month.
Does Bunny co-term add-ons automatically?
Yes. New subscriptions on an account are co-termed with the existing one by default, prorated to the shared end date and rolled into one renewal quote. See Bunny renewal management.
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