UPDATE: The Internal Revenue Service said late Wednesday that homeowners can only deduct prepaid property taxes from their next income tax filings if those property taxes were assessed and paid during 2017. Most Washington-area jurisdictions say they have not yet sent out property tax bills for the coming year which, according to the IRS, would mean property owners can not pay in advance and then claim a deduction before a new federal cap on deductions takes effect.

In other words, thousands of homeowners who scrambled to prepay their 2018 property taxes this week may have done so in vain.

The federal tax legislation that takes effect Jan. 1 will cap the state and local deductions on federal tax returns at $10,000. Residents who planned to pay next year's taxes before this year ends were hoping their efforts will allow them to take advantage of the deductions one last time. Here is a roundup of what each jurisdiction was allowing residents to do:

Although it is impossible for residents to know the precise amount of their 2018 property taxes, regional leaders recommend making an estimate based on last year's amount. To prepay property bills, residents must not have any unpaid tax bills from years prior.

This post will be updated as soon as possible with more information.

Alexandria

The city of Alexandria says it has fielded a rush of calls about prepaid tax options ahead of the new tax bill taking effect. By Tuesday afternoon, the city had already received $1 million in prepayments — far more than in most years, according to Craig Fifer, a spokesman for the city.Payments will be accepted through Dec. 31. The city says it prefers to receive payments by check, with "prepayment" written in the memo field.

Arlington

The Northern Virginia county warns that it cannot offer any tax advice but says it does accept prepaid tax payments. County Treasurer Carla de la Pava told the website ARLNow.com that it has received an unprecedented volume of prepaid payments in the aftermath of the tax bill's passing. De la Pava said the treasurer's office puts the deposits in "very safe" investments, which earn a small return for the jurisdiction. The county says it accepts payments on "active Real Estate" accounts. Residents are asked to email treasurer@arlingtonva.us or call 703-228-3090 with questions.

Fairfax

This Northern Virginia county extended office hours the last week of December to accommodate the potential uptick of people prepaying their taxes. Residents can make their payments in person at 12000 Government Center Pkwy., Suite 223, on Wednesday, Thursday and Friday between 8 a.m. and 6:30 p.m. Payments can also be made electronically.

Loudoun

Residents of this Virginia county can prepay their taxes by mailing a check or paying with cash or credit card at one of the county's two treasury offices in Leesburg and Sterling. Payments must be received by Friday.

D.C.

The District says that people can prepay their taxes online at taxpayerservicecenter.com or at any D.C. branch office at Wells Fargo. Wells Fargo will accept payments via check or credit card. Residents must bring their 2017 real property tax bill to the branch office for their payments to be processed. Payments must be processed by Saturday. (Some Wells Fargo outposts are closed Saturday.) The city is urging residents to avoid mailing payments. in case they are not received in time.

Montgomery

The Maryland county passed last-minute legislation Tuesday that would allow residents to prepay their 2018 property bills. Residents are encouraged to mail their prepayments with a signed copy of a Notice of Intent that can be found online. Payments must be postmarked by Dec. 31 and mailed to the county's Treasury Office, 255 Rockville Pike, Suite L-15, Rockville, MD 20850.

Prince George's

The Maryland county doesn't currently permit prepaid real estate taxes, but the county council announced Wednesday that it will reconvene Thursday to consider emergency legislation that would allow for prepayments. The session will start at 11 a.m. in the County Administration Building, 14741 Governor Oden Bowie Drive in Upper Marlboro.