UPDATE, 6:25 pm: Several procrastinating readers have alerted WW that the arts tax website—the city's preferred method of payment—has crashed. It could not handle the volume of people trying to pay on the last day before a promised $20 penalty.

"At this point the deadline to pay the Arts Tax will be extended until the problem is resolved," the site reads. "We appreciate everyone's patience with this situation."

The city does not say how long it is extending the deadline. —A. Mesh

ORIGINAL POST, 2:05 pm: A surprisingly high number of Portlanders—220,000—have filed returns for the controversial $35 arts tax voters approved last November. Some of those who have filed are exempt from payment but those who have paid have coughed up $6 million, which is 70 percent of the amount originally expected this year.

Considering the tax is brand new and the subject of much confusion and some litigation, that's a strong rate of compliance.

Today is the deadline for payment, according to a press press the city issued this afternoon:

The deadline for Portland residents to file their 2012 Portland Arts Tax returns is today, May 15. Tax returns and payments will be considered timely if postmarked with today’s date, or filed online by midnight tonight. To file and pay online, visit www.portlandoregon.gov/artstax. Taxpayers can also file and pay in person at 111 SW Columbia Street, Suite 600. The Revenue Bureau will keep its doors open to taxpayers until 7:00 tonight and any taxpayer filing in person by then will also be considered timely. The Arts Education and Access Income Tax (“Arts Tax”) was passed by 62% of Portland voters on November 6, 2012. The tax will fund art teachers and access, and is $35 for most adult Portland residents. As of noon today, the Revenue Bureau has received well over $6 million in Arts Tax payments from more than 220,000 taxpayers, and expects over $7 million by Friday, May 17. The Revenue Bureau previously estimated it would collect $8.6 million by June 30, 2013. â€œI’m pleased that so many Portland citizens have already paid their Arts Tax, and tens of thousands more will pay today,” said Bureau Director Thomas Lannom. “Despite changes and legal challenges, most Portlanders are stepping up and paying the tax on time.” Taxpayers who do not file today may be assessed a $15 penalty. Taxpayers who do not file by October 15 may be assessed an additional $20. All income earning adults in the City of Portland are required to file an Arts Tax form. People and families who earn less than the 2012 federal poverty guidelines must file an exemption form, but are not required to pay any tax. For a family of four, the guideline is $23,050. Exemption details are outlined on the website at www.portlandoregon.gov/artstax. Portland residents can call 503-865-4ART (4278) for more information or to make a payment over the phone. Staff will be available to answer calls until 7:00 p.m.