A Scottish Football Association judicial panel has imposed a ban on the club signing new players aged 21 and over until February 1 next year.
The club cannot sign any player at the moment because of an automatic registration embargo which kicked in when they went into administration on June 19 under what were then Scottish Premier League rules.
Hearts, whose true debt has been revealed as almost £29million, have escaped a monetary punishment.
But their extended transfer ban will be a blow to manager Gary Locke, who only has two outfield players aged over 21.
Hearts were also hit with an automatic 15-point penalty in June and Locke will be unable to immediately bring in experienced players if the club exits administration before the end of the January transfer window.
Joint-administrator Trevor Birch, who attended the judicial panel hearing at Hampden, was disappointed with the added sanction.
In a statement, he said: "The decision to impose a transfer embargo on players over 21 until the end of January is disappointing.
"Whilst I appreciate that the SFA rules state that clubs in administration will face sanctions, Hearts have already had a points deduction and player embargo - and it feels like we're being penalised twice.
"That said, these are the cards that we've been dealt and we'll now just have to get on with it.
"At least the decision gives us clarity and means that the bidders can move forward and focus their attention on refining their proposals rather than worrying about possible sanctions."
In a similar hearing last year, Rangers, before they went into liquidation, were hit with a fine and one-year transfer ban, the latter of which transferred to the newco club when they assumed the SFA membership.
That punishment came as a result of several charges relating to former owner Craig Whyte's decision to withhold tax payments of about £13million.
Rangers were fined £50,000 for suffering an insolvency event and twice that figure for bringing the game into disrepute.
An administrators' report yesterday revealed that Hearts, whose Lithuanian directors have left the club, owe Her Majesty's Revenue and Customs £1.9million.
Locke earlier called for "common sense" to prevail ahead of the SFA disciplinary hearing.
Locke, whose team kick off their Scottish Premiership survival bid at St Johnstone on Sunday, said: "We have got a 15-point deduction and theoretically we have close to an under-20 squad.
"So we have certainly been punished enough as far as I'm concerned.
"But at the end of the day we have done things that deserve to be punished.
"We have to take it on the chin. I hope we get some common sense and they can just let us crack on."
Locke added: "The people who ran the club and made it difficult for us, they are not here any more.
"We are trying to build the club back up. Supporters are doing their bit, I'm trying to do my bit, players are doing their bit, everyone that works behind the scenes is trying their best.
"Hopefully we get today over and done with and look forward as a football club.
"That's all we want, we want to move on and try to compete at the top level of Scottish football, which is where we expect to be."