MARIETTA — The deadline for the majority of Cobb County homeowners to appeal their 2011 property tax assessments is Monday.

Appeal forms can be found on the county tax assessor’s website, www.CobbAssessor.org, under “Forms and Applications.”

Any information concerning the reasons for the appeal or information about the property will assist the review process.

Tax assessments started going out May 6. Specific deadlines for appeals are noted on each individual tax assessment.

All appeals must be submitted in writing and either received by the office or postmarked by the U.S. Postal Service within 45 days of the notice date.

Metered mail and other non-USPS canceled mail received after June 20 cannot be considered as timely filed.

“This is very important as the tax assessors’ office does not have the authority to extend state-mandated deadlines,” said Phil Hogsed, chief appraiser for the Cobb County Board of Tax Assessors.

After the appeal is received, the office will send a letter notifying the homeowner within two weeks.

Valid reasons for appealing valuations are value, uniformity and taxability.

The tax assessors’ office, located at 736 Whitlock Ave., Suite 200 in Marietta, will be open from 8 a.m. to 5 p.m. Monday.

The office will be closed today for a mandatory county employee furlough day.

Hogsed said the office has received 3,905 appeals so far. In 2010, the office had 3,417 appeals total.

A state law passed in 2010 requires counties to send every property owner an assessment notice every year, beginning in 2011. Previously, most owners only got such notices when their assessment values changed.

Of the 230,347 mailed this year, about 88,500, or 38 percent, showed lower assessments than last year.