La Guardia has hit a new low — sinking to dead last in overall delays compared with other major airports around the country, The Post has learned.

Only 68 percent of total incoming and outgoing flights at La Guardia reported zero delays through June 30. Fewer than 66 percent arrived on time, and only 70 percent took off on time.

Performance for arrivals and departures alike dropped by about 3 percent since last year, according to new statistics from the Federal Bureau of Transportation.

The airport has always lurked near the bottom of the list, but this is the first time La Guardia has hit last place in overall delays.

Meanwhile, service at Newark Airport improved slightly, with arrival performance going from below 66 percent to almost 74 percent. Departures are now on time at a rate of 72 percent.

JFK flights were on time about 74 percent of the time.

“Nothing matters more to passengers than on-time flights,” said Joe Sitt, chairman of the Global Gateway Alliance.