The Saints have made some interesting signings throughout the Premier League era.
They may struggle to compete with some of the bigger clubs in terms of finance, but they've certainly made some intriguing purchases in the past 20 years - and particularly impressive ones since their return to the top flight in 2012.
The Saints' strong final standings in the Premier League have allowed them to buy foreign stars who have blossomed in England, rather than just relying on the youth players emerging from their exceptionally-run academy.
This is their fifth consecutive season in the Premier League, so it should come as no surprise that all ten of their most expensive signings have come in that time.
However, that's not to say it's always a bed of roses for Saints in the transfer market, because some of their signings have fallen well short of the mark.
With help from our friends at Transfermarkt.co.uk, we've analysed the ten most expensive signings in Saints history - ranking them as flops or hits. Lets see if you agree!
Nathan Redmond
The English winger was signed this summer from Norwich City, who were relegated from the Premier League last season.
The 22-year-old had been in fine form for the Saints so far this season, scoring three goals in nine Premier League appearances.
There's still a lot more to come from Redmond though and he's got plenty of potential.
Verdict: Hit
Dusan Tadic
The Serbian is in his third season on the South Coast since signing from FC Twente for £11.9m.
He has been very impressive in his first two Premier League campaigns and is once again looking sharp during the early part of his third season in England.
Some might claim that he's actually been a bargain.
Verdict: Hit
Victor Wanyama
Signed from Celtic in 2013/14, the powerful Kenyan was brought to Southampton to add a bit more bite to their midfield.
The 25-year-old flourished under Mauricio Pochettino on the South Coast and rejoined the Argentine at Spurs this summer, signing for £11m.
Whilst making a small loss on such a good player is disappointing, there's no denying how impressive he was at Southampton.
Verdict: Hit
Shane Long
After a brief and impressive spell at Hull City, Long moved to the other end of the country for £12.5m in 2014/15.
He's scored just 15 goals in 60 Premier League appearances but it's his tireless contribution and work rate for the team that deserves most praise.
He's currently struggling to get into the Saints' first XI because of Charlie Austin's impressive and prolific form, but that doesn't detract from his ability.
Verdict: Hit
Sadio Mane
Mane signed from Red Bull Salzburg in 2014 and played for the Saints until this summer when he transferred to Liverpool for over £30m.
He scored 21 times in 67 appearances for the Saints and is known for his blistering pace and tidy finishing.
Whilst at Southampton, he scored the quickest hat trick in Premier League history, netting three times in two minutes and 56 seconds in a 6-1 demolition of Aston Villa.
Verdict: Hit
Pierre Emile Hojbjerg
Hojbjerg became the Saints fifth-most expensive this summer, joining for £12.75m from German champions Bayern Munich.
The Dane made 17 appearances for Bayern but struggled to break into their first team and chose a move to England.
However, the 21-year-old is yet to feature very often for the Saints, only making four Premier League starts so far this season.
He's only young, so there's plenty of time to establish himself and impress manager Claude Puel. But the midfielder is yet to really make his mark at St. Mary's
Verdict: Flop - but probably too soon to say.
Daniel Osvaldo
Osvaldo signed for the Saints in August 2013 and a lot was expected of the Argentine. The move reunited the striker with Mauricio Pochettino, who managed him during his time at Espanyol.
However, apart from an incredible goal against Manchester City during his first few months, Osvaldo achieved very little on the South Coast and admitted to struggling with the demands of the Premier League.
He was released from Southampton in 2015 and after short stints with Porto and Boca Juniors, unexpectedly retired from football earlier this year.
Verdict: Flop
Gaston Ramirez
Ramirez was purchased from Serie A side Bologna for just short of £13m to enter the top three most expensive Saints stars of all time.
Big things were expected of the Uruguayan and he was linked with some of the biggest clubs across Europe, so it came as a surprise to many that he joined Southampton.
However, he didn't deliver on the South Coast and although originally in Ronald Koeman's plans, once he returned from a loan spell at Hull City, Koeman had changed his mind on the midfielder.
He's now signed for Middlesbrough on a permanent basis.
Verdict: Flop
Virgil Van Dijk
In 2015, the Saints splashed the cash on the Celtic centre-half. He set the South Coast club back £13.5m and although initially struggling to adapt to life in the Premier League, he is now seen as one of the division's best defenders.
Strong aerially and competent with the ball at his feet, the Dutchman has impressed at Southampton and bigger moves are being touted for the near future.
He's netted 25 times during his professional career too - not bad going for a 6 foot 4 defender!
Verdict: Hit
Sofiane Boufal
Boufal is yet to really hit the ground running. He's only made one appearance in the Premier League this season, although he did start this campaign unfit.
However, Southampton's record signing is new to England and probably needs more time to settle.
He scored a wonderful goal last night against Sunderland to help the Saints progress into the quarter finals of the EFL Cup, where they will face Arsenal.
He's still got a lot of impressing to do on the South Coast but there's plenty of potential there.
Verdict: Jury's out.