16,000 Jersey taxpayers have until the end of this month to file their online returns.
The deadline to do a paper return passed at the end of May.
The government is urging these taxpayers to active their onegov accounts as quickly as possible, as some details could take up to five days to verify if the information doesn't match the current records.
A valid passport is also needed.
"As the deadline for filing a 2021 tax return in paper format passed at the end of May, anyone who wants to file their return on time, must now file it online.
If customers haven’t yet activated their onegov account they’ll need to allow enough time to do this, including setting up a digital ID, and time for verification checks. Please don’t leave it to the last minute, as late filers may be liable to a penalty." - Richard Summersgill, Comptroller of Revenue.
45,500 returns have been received by Revenue Jersey so far. 15,500 of those have been completed online.
Anyone who misses the Sunday 31 July deadline could be fined £300.

Details announced of free childcare for two and three year olds
18-year-olds to have access to Jersey social housing
CI ferry operators to work together to improve inter-islands travel
'Show up and play' football games to tackle festive loneliness
New website helps children and families navigate the digital world
More time in Jersey for French day-trippers
Rapist jailed more than two decades after his crime
Jersey Airport to see 20,000 passengers in the run up to Christmas