Allegheny County property tax bills will be arriving a month later this year.

Common Pleas Court Senior Judge R. Stanton Wettick Jr. on Thursday set March 10 as the tentative date for the bills to be mailed.

The county's property tax invoices ordinarily go out Feb. 1, but they have been delayed this year as the county has struggled to complete a court-ordered reassessment.

Despite the mailing delay, residents still will have a minimum of 60 days after statements are sent out to qualify for a 2 percent tax discount. That break may slightly reduce the sting of a 21 percent increase in the 2012 county tax rate approved last month by county council.

About 90 percent of property owners pay during the discount period, deputy treasurer Tom Bradley said following a status conference on the controversial reassessment project.

Now that the treasurer's office has a tentative go-ahead, Mr. Bradley estimated it would take about five weeks to prepare the 375,000 paper bills. The county also e-mails about 175,000 electronic statements.

There are about 550,000 taxable properties in the county.

Acting chief assessment officer Wesley Graham told the judge that new assessments will be mailed today to property owners in the county's eastern suburbs. Reassessment and appeals notices already have been sent to Pittsburgh and Mount Oliver residents. Property owners in the rest of the county will get their new property values by March 2.

Because of the county's failure to finish reassessment by year's end, the new property values will not be used to set millage rates and calculate tax bills until 2013. That will allow time for property owners to challenge their reassessment numbers.

On Thursday afternoon, Judge Wettick issued a court order setting the deadline for making formal assessment appeals for city, Mount Oliver and property owners in the eastern suburbs at April 2. Those same property owners will have until Feb. 15 to request informal hearings if they find mistakes in the description of their property.