Transfer spending ahead of the new campaign has already eclipsed £500 million (€716 million), and with the window open for the remainder of August, last year’s total spend of £835m (€1.19 billion) is set to be surpassed.
Chelsea begin the defence of their title against Swansea City at Stamford Bridge on Saturday. And despite a low-key summer of transfer activity, Mourinho’s side are the bookmakers’ favourites to seal back-to-back triumphs.
But the Blues boss believes the spending power of the top flight - due in part to next year’s bumper TV deal - will make this season’s title race one of the fiercest in recent campaigns.
“Maybe I’m wrong but I think fewer points will win the title,” Mourinho said. “You have a minimum of five title contenders and the other teams get stronger and stronger.
“I think nobody can complain because everyone is investing – you go to Watford, you go to Bournemouth, Crystal Palace, Stoke, every club. Every club has good players so I think it’s difficult for the top teams because of the competitive nature.”
Mourinho, whose side romped to the title last term, cited Yohan Cabaye’s £12m move to Crystal Palace, Georginio Wijnaldum’s arrival at Newcastle from PSV and Max Gradel’s switch to newly-promoted Bournemouth for a reported £7m fee, as examples of the league’s strength in depth.
“There will be more times when the non-title contenders win matches against the title contenders,” added Mourinho.
“It’s also difficult because they have players who could play in our teams – Cabaye could play for Chelsea, Wijnaldum could play for Chelsea, Gradel could play for Chelsea.
“It’s very difficult to win multiple titles. It hasn’t happened in other countries where the domination is clear. In England it’s more difficult and we all know that.”
Meanwhile, Mourinho urged Ruben Loftus-Cheek, the highly-rated England youngster, to take his chance if the opportunity arises this season.
The 19-year-old started for Chelsea in matches against Liverpool and West Bromwich Albion at the end of last season, but he was heavily criticised by Mourinho following a post-season game in Australia.
Chelsea have come under fire for failing to promote English players from their academy through to the first team.
But asked if homegrown youngsters, such as Loftus-Cheek, feature in his plans for the upcoming season, Mourinho said: “It depends on him not on me. You have to ask him.
“People normally ask about chances and chances and chances and maybe that’s a good excuse for the young players to be where they are.
“I think maybe for the good of English football, you should go the other way. Are you ready to get the chance? Must the manager give confidence to a player? Or must the player give confidence to a manager?
“I had this nice internal discussion with my people. At the end of the day we arrive into a conclusion that players pick themselves. That’s the responsibility that they must have.”
“We’re in England so it’s quite fair that people are trying to get solutions for more local players.
“But you know, I’m a coach. I’m not an office man and for me, as a coach, I think that the players they must give confidence for me to say ‘Let’s go’. Not the other way.”