The Office for National Statistics (ONS) said gross domestic product was up 0.8% in the July-to-September period compared with the previous quarter, confirming its previous estimate.
But it revised its growth figures for earlier quarters.
This means the estimated annual growth rate has now risen from 1.5% to 1.9%, a revision that has surprised economists.
A Treasury spokesman said: "Today's data show that the recovery has been stronger than previously thought and that the government's long-term economic plan is working.
"But risks remain and the job is not done, so the government will go on taking the difficult decisions needed to deliver a responsible recovery for all."
Good news on jobs and growth has to be set against the fact that the recovery has not yet fed through into household incomes, an increasing current account defecit, and the fact that public finances, although the defecit is substantially smaller than under the previous government, are still nowhere near good enough.
ONS data showed that Britain's current account deficit - the difference between the money received from exports and imports - widened sharply in the third quarter to £20.7bn, up from £6.2bn in the second quarter.
And public finances weakened in November, with public sector net borrowing - excluding the effect of bank bailouts - rising to £16.5bn, up from £15.6bn compared with the same month last year.
Despite the strengthening economy, underlying public sector net debt rose to a new monthly record of 76.6% of gross domestic product.
Most recent data has confirmed a strong pick-up in economic activity, which is feeding through to employment levels and government receipts.
On Wednesday, figures showed that the unemployment rate had fallen to 7.4%, its lowest level since 2009.
The number of people out of work fell by 99,000 to 2.39 million in the three months to October, the ONS said, while the number of people in work rose to a record 30.09 million.
Central government receipts from VAT and income tax were up 4.6% to £41.2bn, while the stamp duty take rose 23%, largely thanks to the revival of the property market.
Inflation is running at 2.1%, close to the centre of the target band, 2%