Many of the fans arrived in England around the same time the team did ahead of Sunday morning's clash with the Jacksonville Jaguars at Wembley Stadium.
And if there's still doubt to the lengths any Texans fan will go to scream for the guys on the field, here are the biggest supporters we found:
WATCH: Traveling Texans' "knees-up" in London
The school teacher from Corpus Christi
In the last 12 years, Debbie Brannon has missed only two Texans home games in Houston. She's a dedicated fan unlike any other.
Brannon said she works side jobs to help fuel her Texans adventure. She celebrated her 50th birthday Friday after landing in London ahead of Sunday's game.
"That's my passion: the Houston Texans. I missed two home games in the last 12 years because my daughter had a baby last year, and this year, I was sick right before leaving for London. I said I can't sacrifice missing London or being sick," said Brannon. "This is my 50th birthday celebration. Go big or go home. There's no better way to spend it than with my Houston Texans."
The die-hard Brit
Texans fans travel far for their favorite team. There's one fan who might travel the farthest. We might as well call Thomas Settle the Texans' biggest and most die-hard fan.
Settle lives in the United Kingdom. He started following the American football team back in 2011. He's clearly hooked.
Every year, he makes the journey across the pond to see the Texans. This year, he's going to at least six Texans game, including Sunday's London game. He says often people don't understand he's from Europe and travels to the United States to see the Texans.
"It takes them like three or four attempts to understand I live in the U.K.," said Settle. "They're like, 'You don't live in Houston?' They ask do I live (in the U.S.)? They don't understand I come from the U.K. It's strange."
Settle said he's waited eight years for this weekend's matchup.
The couple and their intercontinental friendship
We met Pamela and Thomas Irby, a couple who have been to every game for the last five years. This Sunday's matchup in London will be no exception. The Irbys cashed in frequent flyer miles to make the haul to the United Kingdom.
Funny thing. They'll have their own personal guide: Settle.
Thomas said the three met one day outside NRG Stadium in Houston.
"I think my favorite memory is walking around the parking lot at NRG and seeing this guy walking around. I started talking to him. He looked kind of lost," said Thoma. "I said, 'You ain't from around here. Are you?' I could tell with his British accent he was from the U.K."
The Irbys and Settle plan on attending Sunday's game together. Talk about a transatlantic friendship. Seriously.
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