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Proration

Exactly how mid-cycle charges are calculated when your customer upgrades

When your customer upgrades mid-cycle, they get credit for the days they already paid for on the old plan, and are charged for the remaining days on the new plan. Here's how the math works.

The Calculation

Credit = Old price × (days remaining / days in cycle)
Charge = New price × (days remaining / days in cycle)
They pay = Charge - Credit

Example: Simple Upgrade

Your customer is on Starter at $29/mo, paid on January 1.
They upgrade to Pro at $99/mo on January 15 (15 days remaining).

Credit for unused Starter days: $29 × (15/30) = $14.50
Charge for remaining Pro days:  $99 × (15/30) = $49.50
They pay today: $35.00

Next full invoice: $99 on February 15

Example: Upgrade with Extra Seats

When your customer has extra seats, those are prorated too.

Current plan: Pro $99/mo, 5 included seats, $25/extra seat
Your customer has 8 seats (5 included + 3 extra = $174/mo total)

They upgrade to: Business $299/mo, 10 included seats, $20/extra seat
On January 15 (15 days remaining)
Calculation
Credit for plan base$99 × (15/30) = $49.50
Credit for extra seats$75 × (15/30) = $37.50
Total credit$87.00
Charge for new plan base$299 × (15/30) = $149.50
Charge for new extra seats$0 — their 8 seats are now within the 10 included
Total charge$149.50
They pay today$62.50

Notice that your customer's 8 seats are now fully covered by the Business plan's 10 included seats, so they stop paying for extra seats entirely.

Quarterly and Yearly Plans

The same calculation applies — the only difference is the cycle length.

Example

Your customer is on Plan A at $300/quarter (January 1 – April 1).
They upgrade to Plan B at $600/quarter on February 15 (45 days remaining).

Credit: $300 × (45/90) = $150.00
Charge: $600 × (45/90) = $300.00
They pay today: $150.00

Next renewal: May 15

Why Downgrades Aren't Prorated

Downgrades take effect at renewal. Your customer already paid for the current cycle and keeps their plan until it expires. Since there's no mid-cycle switch, there's nothing to prorate and no refund.

Why Free → Paid Isn't Prorated

When your customer moves from a free plan to a paid plan, there's no credit to give — the free plan costs $0. They simply pay the full price of the new plan from that day.

Related

  • Plan Changes — When proration applies and when it doesn't
  • Seats — How seat-based billing works with upgrades
  • Invoices — What invoices your customers receive

How is this guide?

Invoices

What invoices your customers receive and when

Trials

How trial periods work and what your customers experience

On this page

The Calculation
Example: Simple Upgrade
Example: Upgrade with Extra Seats
Quarterly and Yearly Plans
Example
Why Downgrades Aren't Prorated
Why Free → Paid Isn't Prorated
Related