The January to June 2015 period not only saw a record number of passengers on U.S. airlines — each of those six months are included in the top 10 for all-time high passenger traffic across the country.

U.S. airlines had their busiest month ever in June, carrying 66 million domestic and international passengers and March, April and May all rank in the top five busiest months ever in U.S. aviation history. Considering domestic and international passengers separately, the first six months of 2015 were all still among the top 10 busiest for international passenger traffic and March, April, May and June were among the top 10 busiest for domestic passengers.

Though not dramatic increases, the first half of 2015 saw a record number of both domestic and international passengers traveling on U.S. airlines with some 341.5 million domestic and 50.4 million international passengers making trips. This represents a 3.7% year-over-year increase for domestic passenger traffic (more than 12 million more domestic passengers than the first half of 2014) and a 0.5% year-over-year increase for international passengers.

Top 10 Months with Highest Seasonally-Adjusted Domestic and International Passenger Enplanements (millions)

RankMonthSeasonally-Adjusted enplanements (millions)
1June 201566.03
2May 201565.9
3April 201565.52
4March 201565.26
5August 200764.86
6October 200764.69
7January 201564.69
8February 201564.63
9September 200764.43
10November 200764.4

Half-Year U.S. Airlines International Seasonally-Adjusted Passenger Enplanements (millions)

Month2012201320142015
January7.747.958.318.4
February7.828.088.298.37
March7.878.028.358.37
April7.867.998.48.38
May7.828.068.398.43
June7.798.138.378.5
Total:46.948.2350.1150.4

Half-Year U.S. Airlines Domestic Seasonally-Adjusted Passenger Enplanements (millions)

Month2012201320142015
January53.453.8854.4156.3
February53.6654.8354.6156.26
March53.2553.1955.3556.89
April53.5753.6154.9257.14
May53.1353.4955.0557.47
June53.3353.7854.9257.33
Total320.34322.78329.26341.5

Source: U.S. Bureau of Transportation Statistics

Photo Credit: U.S. airlines had their busiest six months ever between January and June 2015. Pictured here are passengers walking through Los Angeles International Airport. Jonathan Alcorn / Reuters