Moderator, Marriott Bonvoy & FlyerTalk Evangelist
Join Date: Oct 2002
Location: McKinney, TX, USA
Programs: United Silver; AA Plat/2MM; Marriott LT Titanium; Hilton Gold
Posts: 11,773
Slim. The US Signature card and the US Premier card give 10 and 15 nights respectively and they are not stackable. So I doubt that Marriott would let the Canadian and US cards be stackable.