Section 125 of the Constitution Act, 1867 immunizes federal Crown property from provincial and municipal taxation, which means properties owned by the Government of Canada (including office buildings, airports, ports, military installations, post offices, and federal courthouses) cannot be directly assessed and taxed by host municipalities. The Payment in Lieu of Taxes Act and its predecessor legislation set up a voluntary federal payment regime that delivers payments to municipalities equivalent in scale to what taxes would have been if the property were taxable, without compromising the constitutional immunity.
The mechanics work through a parallel assessment process administered under the PILT Act. The Minister of Public Services and Procurement (operating through Public Services and Procurement Canada) is the federal authority responsible for determining the property value and effective tax rate that would apply if the property were taxable, and then making the corresponding payment to the municipality.
Importantly, the Minister is not bound by the local assessment authority's determination; the federal valuation can and frequently does differ from the value a municipal assessor would have struck. The same is true for the effective rate: the federal authority can adjust the tax rate applied to reflect federal property characteristics that the local rate would not capture.
Disputes between municipalities and the federal Crown are routed to the PILT Dispute Advisory Panel, an independent body that hears representations from both parties and issues a recommendation to the Minister. The Panel's recommendations are not binding (the Minister retains discretion to accept, modify, or reject them), but the Panel's analyses are regularly cited as persuasive authority and have shaped federal practice on contested issues including airport valuation methodology, port property treatment, treatment of leasehold improvements, and the application of business occupancy taxes.
Municipalities that contest a payment determination should expect a multi-year process; sophisticated municipal practice routes the matter through legal counsel with PILT-specific experience and engages assessment professionals to develop a parallel valuation analysis from the municipal perspective.