Williams left Melbourne City to join Haladas Szombathelyi in January 2016.
The forward, who has two caps for the Socceroos, scored 17 goals in 48 appearances in the OTP Bank Liga.
Williams told FourFourTwo he has yet to sign with any new club for next season.
"I haven't signed anywhere just yet," he said.
"Just having a holiday at home then I'll see what will be my best option."
Williams hails from Brisbane and broke into the A-League with the Roar in 2006.
He has had spells with Danish club Brondby along with Australian sides North Queensland Fury, Sydney FC and Melbourne City.
The 30-year-old has represented Australia at Under-17, Under-20, Under-23 and senior level.
On Instagram the striker posted: "It's time for me to say goodbye to Haladas. Thank you Haladas fans you are unbelievable, amazing and so passionate (easily the best in the league)."