The Community Security Trust (CST) - which monitors anti-Semitism among the Jewish community in Britain - said the 892 incidents was a 10% increase on the same period last year when the figure stood at 810.
Incidents recorded included anti-Semitic graffiti left at the home of Holocaust survivors, "Gas the Jews" written on a footbridge in Liverpool and 85 assaults, including punches, kicking or objects being thrown.
More than a third of the incidents involved social media, with CST chief executive David Delew saying: "The problem is spreading across the country and online, it reflects deepening divisions in our society and it is causing increasing anxiety in the Jewish community."
The 323 reports of anti-Semitism online compares to 221 in the same period last year and included one tweet where a user asked people to help "co-ordinate super secret plans to finally get rid of all (Jews)", and another where a comparison was drawn between Nazis and Jews in reference to the Gaza Strip being a "concentration camp".
The report from the CST, which has recorded anti-Semitic incidents since 1984, said it was not clear if an increasing number of incidents was a result of better reporting or increased levels of abuse.
"The answer likely lies somewhere in a combination of the two," it said.
Two-thirds of the 892 anti-Semitic incidents recorded by CST in the first six months of 2019 took place in the UK cities with the largest Jewish populations: Greater London and Greater Manchester.
The report also makes reference to the Labour Party, saying that 55 incidents related directly to the Opposition in February and March.
Allegations of anti-Semitic attitudes have been made against Labour's leadership in recent months, with MP Ian Austin leaving the party with a broadside, saying there was a "culture of extremism, anti-Semitism and intolerance".
The report said: "The highest monthly totals in the first half of 2019 were February and March, with 182 and 169 anti-Semitic incidents respectively.
"These are the joint-fourth and sixth highest monthly totals ever recorded by CST. They occurred when issues relating to Jews and anti-Semitism were prominent in news and politics due to the continuing controversy over anti-Semitism in the Labour Party.
"February saw several MPs leave the Labour Party, some of whom cited anti-Semitism as a prominent reason for their decision. CST recorded 25 anti-Semitic incidents in February and 30 in March that were examples of, or related to arguments over, alleged anti-Semitism in the Labour Party.
"These 55 Labour-related incidents from February and March comprised over half of the 100 such incidents recorded by CST during the first six months of 2019."
Last month, Labour's ruling body accepted Jeremy Corbyn's plans for speeding up the way complaints of anti-Semitism are dealt with.
The National Executive Committee, meeting in London, agreed to endorse the proposal to allow fast-track expulsions in the most serious cases, a party spokesman said.