Southern England saw not only its driest July since data began but also its driest month ever recorded, the Met Office said.
Just 1.9mm rain was measured across this part of the country, narrowly beating the previous record low of 2.0mm in February 1891.
Last month was also the driest July for England and Wales since records began in 1836, according to provisional figures released.
England saw just 6.5mm of rain across July, or 10% of the long-term average for the month, less than half of the previous record of 13.4mm set in 1911.
Wales had 9.3mm of rainfall, or 9% of the average, again well below the previous record of 22.6mm set in 1911.
Northern Ireland saw its eighth driest July, with 26.9mm of rain, the equivalent of 30% the average for the month.
Scotland was the only nation not to trouble the record books last month, with 69% of its average rainfall.
The UK as a whole experienced its third driest July, with 28.9mm of rain: the lowest figure for the month since 1868.