In a public match or a split-payment private match, every player, including the player who created the match, pays only their own share. Nobody is ever charged for empty or unpaid places. If the match doesn't fill up in time, your automatic cancellation rules cancel it and refund the players who paid.
How match payments work
Each player pays their own share when they join. Their card is held for that amount and charged about 4 hours after the match ends. If the match ends more than 6 days after they joined, it's charged 6 days after they joined instead.
The player who created the match is not held for the other places. This is different from a pay your part court booking, where the lead booker is held for the whole court. See "How do pay your part court booking payments work?".
A private match paid in full is different: the player who creates it pays for the whole court, and it is never cancelled automatically.
If the match doesn't fill up
Public matches and split-payment private matches follow your automatic cancellation rules under Settings → Rules & Limits → Auto-Cancellation.
If not enough players have joined by a threshold, the match is cancelled automatically and everyone who paid is refunded in full.
See "How do automatic cancellation rules for matches work?".
Example: two players paid, two aren't on Nettla
Two players have joined and paid in the app. The other two are friends who aren't on Nettla.
The two missing shares are not charged to the players who paid.
Unless the match is full, it is cancelled automatically when it passes your threshold for 2 players (by default 4 hours before the start), and the two players are refunded in full.
To keep the match, the missing players need to join in time. They can create a Nettla account and join, or you can add them yourself.
Add players who aren't on Nettla
Go to Calendar → Schedule and click the match.
Click Add player.
Search for the player, or enter their email and click Add guest.
Choose how they pay: Unpaid, Marked as paid (for example, paid at reception) or Free of charge.
Click Add.
Players you add count towards your automatic cancellation thresholds, whatever their payment status. Add them before the threshold passes.
Good to know
Unpaid players in a match are never charged to another player. Their payment stays Unpaid until they pay, or until you mark it as paid, make it free or cancel it. See "How do I handle unpaid bookings and payment reminders?".
If a player can't make it, they can find a substitute from the match in the app. See "How does player substitution work in matches?".