The donation limit was among the details of the race announced today by the party.
Nominations open May 15 and nominees can pay their non-refundable $50,000 entry fee in two instalments.
Candidates will be vetted and introduced at a PC event on June 2, and the last day to withdraw from the race is Aug. 15.
The party already announced voting will take place on Sept. 6 and, if necessary, Sept. 20.
Former municipal affairs minister Ken Hughes is the only declared candidate to date.