This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

Salt Lake City International Airport is one of the nation's most improved for quickly processing travelers arriving from abroad through passport control.

The average wait time in June was 13 minutes, a 23 percent improvement over June of last year, according to a new study of federal data by MileCards.com.

Only two airports showed greater improvement: Boston (up 31 percent) and Honolulu (25 percent).

The improvement in Salt Lake City comes as average wait times across the country worsen, the study said. So far this summer, average wait times nationally at the 41 airports that handle international arrivals are 3 percent longer than they were a year ago, averaging 20 minutes.

The study said 18 percent of international passengers arriving in Salt Lake City in June had to wait more than a half hour for passport control, compared to an average nationally of 20 percent.

For the past 12 months, the study said 13 percent of international travelers arriving in Salt Lake City had to wait more than 30 minutes, and the average wait time overall was 13 minutes. It said the longest waits were between 11 a.m. and noon, and the shortest were between 5 p.m. and 6 p.m.

The study also said that nationally, July and August are the worst months for passport re-entry waits — at 21 and 22 minutes on average.

Sacramento, Calif., had the longest average waits in the country at 33 minutes. California also has five of the 10 worst airports on the list, also including Oakland, San Francisco, Fresno and Los Angeles.

Chicago Midway had the fastest re-entry, averaging just 9 minutes over the past 12 months.

The study recommends reducing waits at some of the busiest re-entry points by downloading the free Mobile Passport Control app for smartphones, which is approved by U.S. immigration officials. It may be downloaded even while passengers are standing in the immigration line.

With it, passengers may take a picture of their passport, take a selfie, enter flight info, and then are ready to go to the Mobile Passport Control lane. The app also will provide access to priority lanes at the customs declaration checkpoint.

However, checkpoints at only 13 airports currently use the app, and Salt Lake City is not one of them. Airports that use it include: Atlanta; Chicago-O'Hare; Dallas-Ft. Worth; Denver; Fort Lauderdale and Miami, Fla.; Minneapolis, Minn.; Newark, N.J.; New York Kennedy; Orlando, Fla.; San Francisco, San Jose, Calif.; and Seattle.