DAYS out from St Kilda's return home to Moorabbin, the AFL has warned they must get their house in order.

The Saints will move into their new facilities this month, in time for the start of the season.

St Kilda's unsuccessful move from Moorabbin to bayside Seaford, near Frankston, lasted less than a decade.

While they are celebrating the return to Moorabbin and also now have a better deal at their Etihad Stadium home ground, the AFL wants to see financial results.

The Saints, Brisbane and Port Adelaide are the three clubs carrying the heaviest debt.

AFL chief executive Gillon McLachlan said St Kilda's bad debt runs at more than $10million.

"St Kilda have dealt with a whole series of challenges, but it's incumbent on them now to get their P and L (profit and loss) working," McLachlan said.

"They have to get their business to work now."

The Saints are also about to start a pivotal season on the field, with club legends Nick Riewoldt and Leigh Montagna newly-retired.

They finished 11th last year, a game plus percentage outside the top eight.

While there were some strong signs, topped by their round-16 mauling of eventual premiers Richmond, they were too inconsistent.

The Saints have not made the finals since 2011, Ross Lyon's last season as their coach.

Overall, McLachlan said the 18 clubs had made strong progress with bad debt, reducing it by about $10million last year to $50million.

He has confidence that the Lions are turning their fortunes around and praised the work of coach Chris Fagan and football manager David Noble.