Police and prosecutors have been accused of betraying British Jews as anti-Semitic crime rose for the third consecutive year.
New research suggests suspected hate offences targeting Jewish victims reached the worst level on record in 2016 but the number of charges fell "drastically".
Campaigners say alleged perpetrators were charged in fewer than a tenth of cases and only 15 cases were prosecuted last year.
The Crown Prosecution Service (CPS) said it does not recognise this figure.
Anti-Semitic crimes recorded by police forces around the UK increased by 14.9% in 2016, according to figures provided following Freedom of Information requests.
The total of 1,078 offences registered last year compared to 938 in 2015 and 746 in 2014.
Gideon Falter, chairman of the Campaign Against Antisemitism, which compiled the analysis, said: "The failure of police forces and the Crown Prosecution Service to protect British Jews is a betrayal.
"Britain has the political will to fight anti-Semitism and strong laws with which to do it, but those responsible for tackling the rapidly growing racist targeting of British Jews are failing to enforce the law.
"There is a very real danger of Jewish citizens emigrating, as has happened elsewhere in Europe unless there is radical change."
The campaign's report warned that a consistently elevated level of anti-Semitic crime has become the "new normality" for British Jews since the middle of 2014.
Forces recorded 105 violent offences against Jews in 2016 - which was down by 44% on the previous year, the assessment found.
It said 2016 saw the number of anti-Semitic crimes charged fall by 30.5%, with 89 resulting in charges being brought - or 8.3% of the total number of offences recorded.
The campaign said it had ascertained through a review of its own and other charities' data, as well as press reports, that 15 alleged anti-Semitic crimes were prosecuted in 2016.
The CPS said it is wrong to claim it does not take prosecuting anti-Semitic crime seriously.
A spokesman for the service said: "Last year we prosecuted more hate crimes than ever before - more than 15,000 cases.
"We do not recognise the statistics contained in this report."
"Religiously-aggravated hate crimes display an ugly element of society which can be devastating to victims who have been targeted because of their beliefs.
Home Secretary Amber Rudd said: "Everyone in this country has the right to be safe from violence and persecution.
"We are working together to tackle anti-Semitic hate crime in all its forms and using the full force of the law to protect every person in the UK."