An imminent change to how online sales taxes are collected stands to devastate Round Rock’s municipal finances and upend its nearly 30-year-old incentive agreement with Dell Technologies that brought the computer maker to the suburb just north of Austin in 1994.

That's according to a recent lawsuit filed by Round Rock against Texas Comptroller Glenn Hegar, which contends the change Hegar plans to implement Oct. 1 constitutes "an invalid and illegal rule" that will topple longstanding state policy.

"The resulting harm to Round Rock and its citizens is a drastic reduction of millions of dollars of sales tax revenue annually," the lawsuit states. "Round Rock cannot absorb such a devastating reduction in revenue without cutting its budget and city services, raising property tax rates, or a combination of both."