"All economic indicators are imbued with greater significance nowadays because they are building up to the big event later this year, which is the government’s Autumn Statement."
Hargreaves Lansdown says that expectations were for a surplus of closer to £2 billion, and that the timing of tax receipts has helped to boost the figure reported.
Additionally, while public sector borrowing so far this financial year is down by around £3 billion annually to £23.7 billion, the rate of deficit reduction has been slower than OBR forecasts in March.
The ONS also noted that although this is the first post-EU referendum data, "any post-referendum impact may not become clear for some time".
The UK now owes a total of £1.6 trillion, equating to 82.9% of GDP.
Last month, George Osborne abandoned his target to restore government finances to a surplus by 2020.
Osborne said that following the Referendum vote, the government had to be "realistic about achieving a surplus by the end of the decade".
Laith Khalaf, senior analyst at Hargreaves Lansdown, commented: "July is normally one of the bumper months for tax receipts, because HMRC gets a lot of payments of income tax from self-employed people, and also quarterly corporation tax payments from companies, which is why the government found itself quids in last month.
"Of course the elephant in the room is Brexit, and what effect this will have on tax receipts going forward, but so far the hard economic data has actually been pretty robust, though it’s obviously very early days.
"All economic indicators are imbued with greater significance nowadays because they are building up to the big event later this year, which is the government’s Autumn Statement. That’s when we’re going to find out whether the new Chancellor is going to turn austerity off, and turn the spending taps on, in a break with the fiscal policy course plotted by his predecessor, George Osborne. That could well see previous borrowing targets thrown out of the window, if the new government decides supporting the economy is more important than keeping a lid on debt."
