We're being urged to get check our 2019 ITIS rate, request tax refunds or update our addresses before the end of the year.
The Taxes Office is warning of disruption in January, as the department relocates to La Motte Street.
More than 120,000 paper files will be moved, and a new computer system introduced.
Comptroller of Taxes, Richard Summersgill told Channel 103 that anyone who puts off their query will face a wait:
"We're trying to get as many people who would normally come to us in January to come in December instead. If you do come in January, we'll be able to give you very general advice, take your details and put your query in a queue. We'll work through it once the new system is up and running."
Businesses with new employees starting in January are being asked to arrange for them to register for tax before the end of December.
You can find out more about the disruption on Gov.je.
£75,500 raised in Jersey Christmas Appeal Charity Auction
Government to announce support option for carers
Drink driving can cause 'life-changing' consequences
Parked cars damaged in Victoria Avenue crash
L'Ecume II: Lewis Carr jailed for 20 months for fatal collision at sea
Guernsey's former Chief Minister admits making indecent images of children
Minister approves 42 sheltered homes at nursing home
Jersey potato farm to be the site of Channel Islands' largest roof solar array
