The best source of information on the population status of Franklin's Gull is the Breeding Bird Survey (BBS). Although it is not optimal for colonially nesting species and has only medium precision, it provides good coverage of the Canadian range and has medium reliability overall. The national BBS trend shows a sharp decline throughout the 1970s, fluctuation around a low level for the next 25 years, and then an accelerating increase since around 2010. Although the most recent data indicate that the population remains 34% below 1970 levels, representing a moderate decrease, it is likely that the long-term trend will soon be within the range of little change if the recent trajectory persists.

The goal for Franklin's Gull is to increase the population to the level it was at in the early 1970s, based on the Breeding Bird Survey. Trend data show that Franklin's Gull is currently below its goal range, but it has shown an increase over the past decade. Analysis of recent trends and potential growth rates suggests that Franklin's Gull could reach its population goal by 2050 with the support of conservation action.