Ontario lot-and-concession descriptions vs DLS
Ontario lot-and-concession descriptions and Prairie DLS descriptions both identify land, but they come from different survey histories.
Named townships versus numbered townships
Ontario uses lot and concession numbers inside named geographic townships and counties. DLS uses numbered townships, ranges, sections, quarters and meridians.
That difference matters when decoding: an Ontario description needs names such as Mono Township or Dufferin County, while a DLS description needs township, range and meridian values.
What the fields mean
In Ontario, the lot and concession locate land inside a local survey fabric. The named township is not the same thing as a DLS township number.
In DLS, the township is a numbered row in a rectangular grid. The range and meridian determine the column and reference line, then the section and quarter narrow the location.
When to use each decoder path
Use the Ontario path when the description includes a lot, concession, geographic township or county name. Use the DLS path when it includes quarter, section, township, range and a W meridian.
If a description mixes terms from both systems, preserve the original text and verify it against the title or land record before treating it as a mapped parcel.
Last reviewed June 2026. General information about survey systems — not legal, title, or survey advice.
Sources: US BLM — Cadastral Survey (PLSS), Natural Resources Canada — About Canada Lands surveys.