The two systems have been struggling with regulatory issues for some months now, with an original target closing of mid-2023 delayed.
Both systems will have the opportunity to extend the Jan. 24 deadline by subsequent periods of three months by mutual consent.
Parkview Health had revenue of $541 million for fiscal 2023 ending June 30, recording an operating loss of $22.3 million, according to the filing.
UCHealth, a 12-hospital system, has said it will invest $200 million into Parkview once the transaction closes.