Pittsburgh and Allegheny County officials are working out final details of an agreement to merge their accounting systems in time to meet a Sept. 20 deadline.

A deal for the city to replace its out-dated accounting system with the county's modern one has been discussed for about two years.

The deal would cut expenses for both the city and the county and open the way for similar cost-sharing arrangements with independent authorities and other government agencies, county Controller Mark Patrick Flaherty said today.

Pittsburgh Controller Michael Lamb said he, too, is confident the city and Allegheny County will reach consensus on final terms soon.

Signing the deal by Sept. 20 would allow Pittsburgh to submit its proposed budget for next year to the Intergovernmental Cooperation Authority, which oversees the city's finances, by a Sept. 22 deadline. It also would meet a Sept. 21 deadline for presenting the first version of the county's 2011 budget to county council.

Negotiations over the merged accounting system have involved the two controllers and the offices of Pittsburgh Mayor Luke Ravenstahl and Allegheny County Executive Dan Onorato.

The proposed cost-sharing deal would have the city reimburse the county for its actual costs in setting up and maintaining a joint accounting system, Mr. Lamb said. "We are close to a deal," he said. "I feel confident that we will have a favorable answer for the county and will move forward."

The biggest benefit to the county and its taxpayers would be that the costs for maintaining the financial accounting system will be spread out between both governmental units, Mr. Flaherty said.

The city would be responsible for hardware costs and software licenses to expand the county system to allow it to meet the city's needs as well. Those one-time expenses might total about $2.8 million, Mr. Flaherty estimated. The city's share of annual maintenance costs would be about $500,000, he said.

For the city to create a similar system on its own would cost $10 million to $12 million, he said. Annual operating costs also would be higher, he said.

"This is the way to the future to reduce costs for taxpayers," he said.

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