"It's a nice club and a club with a big history. I saw a lot of Everton games last season and they have a strong team," he told evertonTV.
"I spoke with the manager earlier and the feelings were good.
"The training ground is really good and it's a typical English stadium and I love it.
"I haven't spoken to Steven yet because he is away with his national team, but I will speak to him soon.
"I am looking forward to linking up with him again because he is a good player."
Everton have paid £6.2m, which could rise to £7m on appearances. Heitinga returned to John Lennon Airport for a flight to Holland to join up with his international colleagues.
Everton chief executive Robert Elstone said: "We are pleased the deal has been completed to get John into Everton. He is a very experienced player having played at both Ajax and Atletico Madrid and I know David Moyes is looking forward to getting him started."