Aimee Christopher, who runs the Airport Cafe on St Mary's, has said she is "amazed" by the generosity of islanders.
The cafe's Christmas Market last weekend has so far raised £1,400 for the RNLI, with more money to come in.
The event featured 18 stalls and Luke Paulger provided free shuttle buses to the airport from the Town Hall.
Aimee told This is Scilly News: "The market went really well, This year we decided donate the raffle money and stall table rent to the RNLI. So far we are at £1,400 and Luke and his men still have the buckets they had in their buses to count.
"I’m just amazed at how wonderful and generous everyone is over here. I'd like to thank all of the local business for donating some incredible prizes and also Rachel Keeley and my mum Jill Christopher for selling the tickets and working like troupers!"
St Mary's RNLI coxswain Pete Hicks said: "It's so humbling to know that the community supports the RNLI and our lifeboat here and can raise £1,400 for the charity. Thank you very much!"