Moonbase can only hold your balance in EUR or USD. There is no GBP holding currency. Per their help centre, that has two effects:

• If you set a GBP price, you pay a 3% currency surcharge on every one of those sales (EUR is 0%, USD is 1%), and the money is converted out of GBP before it is held.
• If you don't set a GBP price, Moonbase converts for the buyer and the surcharge lands on your UK customer instead.

For UK-based sellers it is worse, because the money then gets converted back to GBP at payout. So a sale from a UK customer to a UK seller goes GBP to EUR or USD then back to GBP, with a surcharge on the way.

I asked Moonbase about it. Tobias @tobbentm replied quickly and opened a feature request, but said there is no timeline yet:

https://feedback.moonbase.sh/p/gbp-as-holding-currency

It's been open since the end of August and has two votes, one from me and one from Tobias. I suspect that's because nobody knows it exists, not because nobody cares.

The UK is a big market for plugins, and I guess most sellers here have a decent share of UK buyers. For me it's about 35%.

If this matters to you, an upvote and a one-line comment with your rough GBP split would help them prioritise it.

For context: I'm not on Moonbase yet. I'm planning a move from Gumroad, Moonbase is where I want to end up, and this is one of the few things holding me back. So this isn't a complaint about them. They have been responsive, and this is the kind of thing a vote count can move.