Beyoncé and Jay-Z planned a surprise proposal for Lil Rel Howery at the Renaissance tour — but he almost missed it going to the bathroom

• Beyoncé, Jay-Z, and the singer's mother, Tina Knowles, helped Lil Rel Howery plan his proposal.
• Howery said on "The Tonight Show" that he initially asked Tina Knowles for advice.

Beyoncé and Jay-Z helped actor and comedian Lil Rel Howery propose to his girlfriend Dannella Lane during the Renaissance World Tour, the comedian said.

Howery popped the question to Lane at Beyoncé's concert at SoFi Stadium in Inglewood, California, on September 4, with the moment shown on the big screen for the whole audience to see.

However, during his appearance on Monday's episode of "The Tonight Show Starring Jimmy Fallon," Howery said he almost messed up the plan because he went to the bathroom.

Howery said he got in touch with Beyoncé's mother, Tina Knowles, to pull off the surprise proposal to Lane at the gig.

"I got the tickets last minute but I called Miss Tina because I want to make sure I propose to the right song," Howery said. "And so I'm like, 'Uh Miss Tina, what's the perfect song to propose to?' And she was like, 'Well, do it to "Love On Top."'"

On her recent tour, Beyoncé stopped singing partway through the ballad, allowing the audience to serenade her with the chorus instead.

"I was like, 'Alright, that's going to be perfect. That's when I'm going to do it.' And she was like, 'Well, I told Jay that you was proposing and he suggested that we could put it on the jumbotron for you,'" Howery recalled. "I was like, 'Woah, wait a minute now.' You know there's already pressure proposing."

"I didn't ask for all the other stuff that came with it," the "Free Guy" actor said. "I was just calling to ask for a song and everyone else was like, 'Do the jumbotron.'"

Howery said that Beyoncé agreed to the plan, but because he wasn't aware of the setlist, he wasn't sure when she would perform the song.

At one point, he went to the bathroom — which is exactly when the intro to "Love On Top" began playing.

"By this time, the crowd is singing. This is my part. So I run in, run out, retrace my steps," Howery said. "I end up finding the seat because I can see the cameraman sweating, on his earpiece like, 'I don't know where he at.' And then the crowd started to get irritated because they'd been singing the a capella for so long."

Howery said that Beyoncé herself also gestured for him to hurry up from the stage, prompting the comedian to get down on one knee and propose.

Howery and Lane both shared videos of the proposal on Instagram and thanked Beyoncé, Jay-Z, and Knowles for their help.