Pickford's position with the national team has come under scrutiny following the impressive form of Arsenal goalkeeper Aaron Ramsdale this season.
Pickford is fighting relegation with club side Everton this term and has conceded 44 goals in 25 Premier League appearances.
Ramsdale withdrew from the latest England squad due to injury and Pickford was chosen to start against Switzerland in a friendly game at Wembley on Saturday.
The 28-year-old impressed as England won 2-1 thanks to goals from Luke Shaw and Harry Kane, and Southgate reserved special praise for Pickford afterwards.
"He's always played well for us and he has a good focus with us," Southgate told a news conference.
"He has a very good relationship with [goalkeeper coach] Martyn Margetson, who I think does an excellent job with him. So, he knows the structure around him. He knows clearly how we want him to play.
"There is competition for everybody's position and that's what we want. We don't want people just sitting, thinking confidently that there's no competition that doesn't help a team.
"I think the form of the other goalkeepers is important. But he showed again, big saves at important moments."
"I thought he was very calm with the ball," added Southgate. "That allowed us to relieve the pressure by going back and out of the press.
"Of course, he's got every club in the bag because he can go long, which is a problem for teams as well. So a very good performance from him, especially the saves in the first half."
In 43 caps for England, Pickford has kept 20 clean sheets.
