Huddersfield have triggered a clause to sign on-loan Mainz goalkeeper Jonas Lossl on a permanent deal this summer.
Huddersfield have not disclosed the fee involved or the length of contract agreed.
"The fact that Jonas will join the club permanently in the summer is excellent news for Huddersfield Town, following on from the boost that Florent Hadergjonaj will also become a full-time Terrier last week," manager David Wagner said.
"We knew that Jonas had big quality when he joined us on loan and that has certainly proven to be the case. The quality of his distribution has been perfect for the way we play, but he's also made big, big saves at important moments. I also think we've seen him improve as the season has gone on.
"He's been a huge part of our season so far, on and off the pitch, and I'm sure he'll continue to be as we aim to retain our status in the Premier League."