Average prices in the area rose by 4.1%, according to Land Registry figures – contributing to the longer-term trend, which has seen property values achieve 22.3% annual growth.
The average house price in the area in May was £128,266 – with values rising by an average of £23,000 over the last year.
The figures show that owners of detached houses saw the biggest improvement in property prices in Hartlepool in May. They increased by 4.5%, to an average of £222,087 - 23.2% up over the last year.
The value of a semi-detached rose by 3.8% over the month – up 21.1% annually – to an average of £130,995.
Terraced home prices were up 4% monthly – and 23.1% annually – to an average of £93,033.
The average price of flats was £69,361 – a monthly rise of 4.4% and up 18.1% annually.
First-time buyers in Hartlepool spent an average of £108,000 on their property – £20,0000 more than in May 2016.
Buyers paid 10.4% less than the average price in the North East (£143,000) in May for a property in Hartlepool.
Across the region, average property prices are low compared to those across the UK, where the average cost is now £255,000.
The most expensive properties in the North East were in North Tyneside – £177,000 on average.
The highest property prices in the UK were in Kensington and Chelsea, where the average May sale price was £1.2m.