Add seats now, and what proration costs EN

A charge for the days left in the period. Your renewal date does not move.

If your team grows partway through a billing period, you can add paid seats straight away instead of waiting for your renewal. You pay once for the new seats, covering only the rest of the current period. This is called proration. Your renewal date stays the same, and from that date on you pay for the new seat count.

Before you start

Only the workspace owner can add seats. Admins can see the seat count but cannot change it.
The workspace must be on Pro and set to renew. If the subscription is cancelled, you cannot change its seat count. You will see: "This subscription is cancelled and will not renew, so its seat quantity cannot be changed."
You need to pay by card. PayPal cannot take a mid-period charge, so on PayPal you can only add seats from your next renewal. To add them now, switch the workspace to card payment on the Billing page first. See Card or PayPal: the differences that matter.
No switch between monthly and yearly billing can be booked. If one is waiting for your renewal, cancel it on the Billing page before you change seats.

Add seats

In the dashboard, open Users & Seats for the workspace.
In Seats, enter the new total number of seats you want. Enter the total, not just the number you are adding.
In Change, choose Add now.
Select Update seats. The Add seats payment page opens. Nothing has been charged yet.
Check the Upgrade details panel. It shows the charge and how it was worked out (see below).
Choose a payment method. Your workspace's saved card is offered, or you can enter a new one.
Select Complete purchase, check the summary, and select Pay now.

When you return to Users & Seats, the line above the seat meter reads "Confirming your payment…" for a few seconds. After that the new seats are added, and you can give them to your teammates. See Give someone a paid seat, or take it back.

If you want the extra seats but do not want to pay anything today, choose Add next cycle in step 3. Nothing is charged now, and the seat count goes up on your renewal date.

How the charge is worked out

The added seats are charged at the per-seat rate your subscription already uses, for the part of the period that is left:

New seats and Total seats: how many seats you are adding, and what the workspace will have afterwards.
Days until renewal: the number of days left in the current period.
Rate per seat: the price of one seat for a whole billing period. This is shown per month (/mo) on monthly billing and per year (/yr) on yearly billing.
Subtotal: the added seats × the rate per seat × the share of the period that is left.
VAT: added where it applies, or shown as reverse charge. See Billing details, VAT numbers and reverse charge.
Due today: the amount you pay now.

Under the total, a line spells out the calculation, such as "2 seat(s) × $120.00 for the 182 day(s) left of this period", and gives your unchanged renewal date. The charge uses the exact time left in the period. The day count is rounded up, so even a partial day counts as one.

For example, on yearly billing at $120 per seat per year, adding 2 seats with half the year left costs about $120 plus any VAT. The same 2 seats cost less the closer you are to your renewal.

What happens at renewal

Your renewal date stays the same. Proration only pays for the seats until your current renewal date.
From your renewal, you pay for every seat at the full rate. The panel shows this as "From your renewal, N seats cost…".
Volume discounts start at renewal. If the new seat count reaches a bigger volume discount, the panel tells you. The lower per-seat rate applies to every seat from your renewal, not to today's charge. See Volume discounts and the seat cap.
Adding seats now replaces any seat change booked for your renewal, such as a planned reduction.

Quotes are only held for a short time

The prorated amount gets smaller every day, so a quote expires after about an hour. If you leave the payment page without paying:

Nothing is charged, and the workspace keeps its current seat count.
Until the quote expires, Users & Seats shows "Payment pending — finish adding N seat(s)". Select Continue payment to go back to the payment page, or Cancel change to drop it. You can also select Cancel this change on the payment page itself.
If the quote expires, you get an email saying the seat upgrade was not completed. To add the seats, start again from Users & Seats to get a new figure. See Your checkout quote expired.

PO numbers and invoices

The payment page has an optional PO number field (PO means purchase order). A number entered there is printed only on this charge's invoice, and your workspace's default PO number stays the same. To change your billing address, select Edit next to Billing details. Like every charge, the seat payment has its own invoice. See Find and download your invoices.

Troubleshooting

"A PayPal subscription can only change seats for the next renewal." Choose Add next cycle, or switch to card payment on the Billing page and then add the seats now.
"The price changed while you were confirming, so nothing was charged." Something changed between the quote and your payment, for example a new day started or the subscription renewed. Try again to see the current amount.
"This quote has expired." Nothing was charged. Start the change again from Users & Seats.
"Your billing details changed": you edited your billing details after the quote was made, and your VAT rate changed. You cannot pay this quote. Start the change again from Users & Seats to get a price at the new rate.
"The payment did not go through. Try another card." Your card was declined or the payment was not completed. Nothing was added. Try again with another card.
"These seats have already been added": the payment went through, maybe in another tab. You do not need to pay again.
"This seat change is no longer available": the change was cancelled, or a newer seat change replaced it. Nothing was charged.