Harrah's faces property taxes for the first time since it opened in Chester seven years ago. The casino was built in a Keystone Opportunity Zone, which made it exempt from property taxes until that benefit expired at the end of 2013.
The appeal, filed Wednesday in Delaware County Court, states that the assessment is "excessive, improper, unjust and contrary of the law" because it does not represent the actual value of the casino.
Paul Tannenbaum, a New Jersey lawyer representing the casino, declined to identify the amount he felt would be a fair assessment.
"It's just the beginning stages of the appeal process," Tannenbaum said.
Delaware County's assessment manager did not return a message left Friday.
The county assessment of $218 million translates to a market value of $294 million.
Harrah's has not taken steps to fight its tax bill in Chester City, which has a separate assessment process. The city assessed the casino at $52.5 million, or $210 million in market value.
Casinos in Atlantic City have successfully appealed tax bills in recent years, arguing that their revenue had fallen as competing casinos opened around Pennsylvania. Parx Casino in Bensalem filed an appeal of its assessment that is pending in Bucks County.