PORTLAND, Ore.—Wireless industry vendors that specialize in vetting phone bills might want to call on the state of Oregon.

The secretary of state’s Audits Division this week said a review shows the state could have avoided at least $182,000 in service charges by shifting to lower cost plans for phones that were not used at all during one or more months.

Over the same period, the state had about $270,000 in charges that “significantly” exceeded the base monthly service cost for the phones. Some of the excess cost could have been avoided by shifting to plans that better matched actual use.

The state said it was charged about $3 million by two major vendors during a one-year period for abut 8,145 phones and related services. Sprint Nextel and AT&T provided data for the report, but Verizon did not.

Among the report’s recommendations: The state should work with cell phone vendors to ensure that electronic billing and usage data are available when needed, and state agencies should conduct regular reviews of cell phone bills and vendor reports to identify zero-use phones and usage patterns that indicate a line should be terminated or a plan should be adjusted.

As for missing phones, that state said it could have avoided charges by improving its cell phone tracking processes.