The pair, who are British-American dual citizens, were arrested in late December on allegations of human trafficking, rape and forming an organised crime group, and have remained in custody ever since.
Romanian police are able to keep suspects in custody for 30 days, but this has been extended each month since by local courts.
They will now remain in custody until the end of April.
What are the allegations again Andrew Tate?
Mr Tate was arrested on 29 December, 2022, on suspicion of human trafficking, rape and forming an organised crime group.
His brother, Tristan, and two others were also detained at the same time.
At the time, as reported by Reuters, prosecutors said the group “appear to have created an organised crime group with the purpose of recruiting, housing and exploiting women by forcing them to create pornographic content meant to be seen on specialised websites for a cost”.
Romania’s anti-organised crime agency, Diicot, has previously said it had identified six alleged victims in the human trafficking case who claim they were subjected to “acts of physical violence and mental coercion” and were sexually exploited by members of the alleged crime group.
Diicot also said the alleged victims were lured with pretences of love, and later intimidated, surveilled and subjected to other control tactics while being coerced into engaging in pornographic acts for substantial financial gains.
Both Tate brothers have repeatedly denied any wrongdoing.
As part of the investigation, Mr Tate’s property was raided and, in early January, a number of luxury cars were towed.
Prosecutors have said the assets would be used to cover investigation expenses and victim compensation if they can prove the owners gained money through illicit activities.
Why is Andrew Tate still in custody?
Romanian police are able to keep suspects in custody for 30 days.
However, by court ruling, this can be extended to a total of 180 days before a criminal investigation is closed.
In the case of the Tates, judges have justified keeping them in custody on the grounds that they might pressure witnesses or interfere with evidence, BBC News reported.
The current extension is the fourth consecutive month in jail, hence going through to two-thirds of the legal detention time while the case against the Tate brothers is investigated.
BBC News reported a spokeswoman for the pair, Mateea Petrescu, saying the Tates’ team was “speechless” at the court’s decision to keep the pair detained for a further month.
Continued detention had “irreparably harmed” their images and it would “take years to rebuild their reputation”, she said.