Those are the findings from a survey commissioned by MPs and published on Thursday following allegations about the culture within Parliament.
It also showed that of the 1,377 workers surveyed, 39% had experienced bullying and harassment of some sort while on the estate.
Of those 45% were women and 35% were male.
The survey coincides with the publication of recommendations by a cross-party working group which has examined the problems faced by politicians, aides and parliamentary staff.
Under the proposals, MPs accused of sexual harassment will initially have their names kept secret.
A new behavioural code is also planned for all MPs, peers and staff, which will underpin a new independent complaints and grievance procedure separate from the political parties.
The group, led by Leader of the House of Commons Andrea Leadsom, also proposed dealing with sexual harassment complaints separately to bullying and harassment claims.
Meanwhile, the range of sanctions for offenders includes written apologies, mandatory training and future behaviour agreements.
For the worst cases, MPs could even face being kicked out of Parliament by voters, while staff would be dismissed.
However, in what is likely to be the most controversial proposal, the new processes will be confidential for all involved until cases are escalated through the relevant parliamentary bodies.
In what are judged to be lesser cases, those accused will have their identity protected until the complaint is finally resolved.
For more severe cases, those facing allegations will only be named publicly once the case reaches Parliament’s Committee on Standards.
A source said: “It is designed to instil confidence for all involved. You won’t have your name splashed in the papers if you make allegations. And you won’t have trial by media if you are accused.”
The proposal to preserve anonymity for those accused, until they are found guilty of wrongdoing, may prompt fears it will stop other potential victims from coming forward.
In some cases, the Westminster scandal saw initial allegations made by one individual encourage other accusers to lodge their own complaints.
The plans will be considered by both the House of Commons and House of Lords with a debate taking place in the last week of February or first week of March.
Caroline Lucas, Green Party co-leader and a member of the cross-party working group, hailed the recommendations as “a blow to patriarchal politics” and a “step change for those fighting sexual harassment and bullying in Westminster”.