The Lafontaine (or La Fontaine) Baronetcy, of the City of Montreal in the County of Montreal, was a title in the Baronetage of the United Kingdom. It was created on 28 August 1854 for the Canadian statesman Louis-Hippolyte Lafontaine. The title became extinct on the early death of his son, the second Baronet, in 1867.
| Escutcheon: | Azure, on a Fess Argent, an open Book surmounting a Sword bendwise proper, between two Maple Leaves Vert, in chief a Cubit-Arm fesswise proper, vested, cuffed and holding a Pair of Scales Argent, and in base on a Mount Vert, a Beaver proper. |
| Crest: | Upon a Rock, a Stone Fountain proper. |
| Motto: | FONS ET ORIGO (Source and origin) |