More than three-quarters of gay, lesbian and bisexual victims of hate crime did not go to the police for fear they would not be taken seriously, a survey has found.

Harassment, insults and intimidation were the most common crimes, reported by more than eight in 10 of victims, according to research commissioned by equality group Stonewall.

Half of those who did report a hate crime to police were not satisfied with the way it was handled. Fewer than one in 10 cases reported led to a conviction.

Homophobic Hate Crime: the Gay British Crime Survey 2012, conducted by pollsters YouGov, surveyed more than 2,500 lesbian, gay and bisexual people across Britain on their experiences of homophobic hate crimes and incidents.

Unveiling the research at New Scotland Yard in London, the Metropolitan police commissioner, Sir Bernard Hogan Howe, said: "The MPS has made improvements in recent years. However, there is no place for complacency and we must continuously strive to enhance the service that LGBT Londoners expect and deserve."

One in 10 people experiencing a homophobic hate crime or incident was physically assaulted while almost one in five victims was threatened with violence or the use of force, the survey found.

One in eight victims experienced unwanted sexual contact and one in eight had their home, vehicle or property vandalised.

The Stonewall deputy chief executive, Ruth Hunt, said: " Despite radical steps to make police forces more accountable to the public, these figures show deeply disturbing levels of violence and intimidation still faced every day by lesbian, gay and bisexual people in Britain.

"The fact that two-thirds of gay people who experienced a hate crime or incident didn't report it to anyone shows the scale of the challenge facing our criminal justice system."

One in six lesbian, gay and bisexual people have experienced a hate crime or incident in the past three years.

Half of victims who reported a hate crime or incident to police said it was recorded with no further action taken, while two in five of those reporting an incident to police said it was not recorded as homophobic.

Alex Marshall, the chief executive of professional standards body the College of Policing, said: "The results of this Stonewall survey provide a significant opportunity to review and improve how the police respond to homophobic hate crime.

"There's still more to do and we are committed to working with forces, police and crime commissioners and wider stakeholders to ensure we play our part in delivering a better service for victims of homophobic hate crime."

Gloria de Piero, the shadow minister for women and equalities, said: "This summer we celebrated the passing of equal marriage in parliament but this report shows us that, while there might be equality under the law, people still face the most appalling abuse and discrimination every day simply because of their sexuality.

"It is shocking that three-quarters of victims of homophobic hate crime don't report the incident to the police and that victims still do not feel they will be taken seriously when they do."