Belgium and World Cup winners France are the first teams to share top spot in the FIFA rankings in the classification's 25-year history.
Roberto Martinez's side, defeated by Les Bleus in the semi-finals at Russia 2018 before claiming third place, overcame Scotland 4-0 in a friendly and won their Nations League debut 3-0 against Iceland earlier this month to join the world champions at the summit.
France, meanwhile, were held to a goalless draw by Germany in Munich before beating Netherlands 2-1 in Nations League Group A1.
Both teams find themselves on 1729 ranking points, well ahead of third-placed Brazil. The World Cup quarter-finalists, who feel at the hands of the Belgians in Russia, have 1663 points to their credit, six more than last month.
The only other change in the top 10 saw Denmark, who played an international against Slovakia last month with a team comprised of amateurs and futsal players, slip down one place to 10th, below Spain.
After their humiliating group-stage exit at the World Cup, Germany rose a further three positions and now sit 12th.
The biggest movers were Ukraine, who climbed six spots to 29th courtesy of Nations League triumphs over Czech Republic and Slovakia.
Meanwhile, Kenya enjoyed the biggest jump in terms of points, moving up 22.
Ghana and Slovenia were the big losers this month, each slipped six spots, to 51 and 61 respectively.