Death, taxes and the Yankees beating the Orioles.

The Yankees made it 13 straight over their feeble AL East foes with an 8-5 win in the first game of Monday’s split doubleheader in The Bronx.

It marked the longest run of success against a team by the Yankees since they won 13 straight against the Twins from 2002-03.

And they hit four more homers in the process, adding to their record number against the Orioles with 56 in just 16 games.

“The home run has been a big factor this year, obviously, around the league and in a lot of ways we’re built around that,’’ Aaron Boone said after his team matched its season-high by going 37 games over .500 (78-41).

“Our guys are capable, when they’re swinging the bats really well, of hitting the long ball. With our group, not a lot surprises me.”

The one flaw in their latest victory came — again — from their starting pitching, as James Paxton barely made it through six innings and allowed two more home runs.

After Paxton gave up a first-inning run for the sixth time in his past seven starts, the Yankees continued to crush Baltimore pitching in the bottom of the frame.

Brett Gardner led off with a walk and a bad play by Hanser Alberto at third let Gardner to reach second on what should have been a routine groundout.

Didi Gregorius made Gabriel Ynoa pay, clobbering a three-run homer to center to make it 3-1 before the right-hander recorded an out. Gleyber Torres then crushed a one-out homer to right to give the Yankees a 4-1 lead.

It was Torres’ 11th homer while facing the Orioles this season. He became the fourth Yankee since 1961 to hit at least that many homers against one team, joining Roger Maris (13 versus the White Sox) and Mickey Mantle (11 against the Senators) — both in 1961 — and Aaron Judge’s 11 versus Baltimore in 2017.

It also snapped an 0-for-14 skid for Torres and the Yankees led the rest of the way.

“It’s nice when you go out and give up a run in the first inning and get it right back,’’ Paxton said.

The left-hander bounced back from his 29-pitch first with an easy second, while back-to-back two-out doubles by Gardner and Gio Urshela added another run in the second.

Trey Mancini tomahawked an 0-2 pitch into the seats in the short porch in right, bringing Baltimore to within 5-2, but Urshela hit a solo shot in the fifth that went an estimated 461 feet. It was Urshela’s seventh homer in his past seven games.

But Paxton’s home run woes continued in the sixth, as Anthony Santander took him deep, the second time a Baltimore hitter homered off the lefty on an 0-2 count.

Paxton slogged his way through a six-inning, three-run performance, hardly inspiring confidence for the stretch run.

“To the Orioles’ credit, they spoiled a lot of pitches today,’’ Boone said.

Cameron Maybin’s two-out shot to left in the sixth made it 7-3 and a Gregorius sacrifice fly an inning later gave the Yankees a five-run lead.

Luis Cessa, who had been excellent in his previous 10 outings — pitching to a 1.32 ERA in 27 ¹/₃ innings — made things interesting in the eighth.

Instead of allowing Boone to rest much of his bullpen, the right-hander allowed a run and left with the bases loaded and one out for Zack Britton. The left-hander walked Jace Peterson to force in a run before getting a groundout from Stevie Wilkerson to keep it 8-5.

Aroldis Chapman closed it for his second save in as many days.