Two towns eight miles apart in the Tees Valley sell homes for almost exactly the same money. Across 2025, the median home in Stockton-on-Tees changed hands for £177,000; in neighbouring Darlington, £179,498 — a difference of under £2,500 (HM Land Registry Price Paid, standard sales, data fetched 22 August 2026). Buy at the middle of either market and the mortgage-plus-council-tax bill lands within about £2 a month of the other town.
Yet one clear difference separates the two housing stocks: energy efficiency. Stockton's homes rate markedly better on their Energy Performance Certificates (EPCs) than Darlington's. And the reason has nothing to do with which town builds better houses — it comes down to when the houses were built.
Same price, near-identical monthly cost
Here is how the two markets line up on price and running cost. The mortgage figure amortises a loan of 75% of each town's median (a 25% deposit) over 25 years at the Bank of England's most recent quoted five-year fixed rate at 75% loan-to-value — 4.32%, as of the April 2026 file. Council tax is the 2026-27 Band D charge divided by twelve. Energy, insurance and maintenance are excluded because they vary property by property.
| Measure | Stockton-on-Tees | Darlington |
|---|---|---|
| Median sale price, 2025 | £177,000 | £179,498 |
| Sales in the sample | 2,906 | 1,706 |
| Median floor area (EPC) | 88 m² | 86 m² |
| Council tax, Band D 2026-27 | £2,589.83 | £2,493.83 |
| Illustrative mortgage (75% LTV, 25yr, 4.32%) | ≈ £724/mo | ≈ £735/mo |
| Council tax per month | ≈ £216 | ≈ £208 |
| Mortgage + council tax | ≈ £940/mo | ≈ £942/mo |
On the two costs that a whole town sets — the price you borrow against and the council tax band — the two are practically interchangeable. A typical first-time buyer would pay £0 stamp duty in either town (both medians sit below the £300,000 first-time-buyer nil-rate threshold), and a home mover would pay £1,040 in Stockton and £1,090 in Darlington (HMRC rates, confirmed against the Homecost calculator on 22 August 2026).
You can see the full cost breakdown for a Stockton postcode or do the same for a Darlington postcode to compare the all-in monthly figures for real streets.
Where they diverge: the energy rating
Look at the EPC band each home carries and the two towns pull apart. Taking the most recent certificate for every address with one on record:
| EPC measure | Stockton-on-Tees | Darlington |
|---|---|---|
| Homes rated C or above | 48.1% | 37.9% |
| Homes rated F or G (the lowest bands) | 1.4% | 2.9% |
| Certificates in the sample | 43,297 | 25,271 |
Stockton's stock is more than ten percentage points more likely to reach band C — the level the government uses as its efficiency benchmark — and only half as likely to sit in the worst F or G bands. For context, the share of homes rated C or above across England is roughly 39.9% on the same "latest certificate per address" basis, so Stockton sits well above the national figure and Darlington a shade below it.
An EPC band is not a heating bill, and the modelled running costs printed on a certificate rest on dated assumptions, so we do not quote them as pounds here. But the direction is well established: a lower-rated home generally costs more to heat and is a stronger candidate for insulation or heating upgrades. If you want the mechanics, our guide to what an EPC rating actually measures walks through the bands, and how much each EPC band typically costs to run sets out the indicative gaps for a standard home.
Build era explains almost all of it
The gap is not a story about location or workmanship. It is a story about the age mix of each town's houses. Group the certificates by the era a property was built and the pattern is unmistakable.
| Build era | Stockton: share of stock | Stockton: % rated C+ | Darlington: share of stock | Darlington: % rated C+ |
|---|---|---|---|---|
| Before 1930 | 11.9% | 19.4% | 35.9% | 12.1% |
| 1930–2002 | 73.6% | 33.6% | 49.2% | 28.4% |
| 2003 onwards | 14.5% | 97.6% | 14.9% | 96.5% |
(Shares are of stock with a dated certificate; a small "undated" group is excluded from the era split.)
Two things stand out. First, within each era the two towns are close: pre-1930 homes rate poorly in both (12–19% reach band C), post-2003 homes rate superbly in both (roughly 97%). Stockton is not building warmer houses than Darlington — the same-age homes score much the same on either side of the boundary.
Second, the mix differs sharply. More than a third of Darlington's homes predate 1930, against barely one in eight in Stockton. Because pre-1930 stock — solid-wall Victorian and Edwardian terraces and villas, built before cavity insulation, double glazing or modern boilers — is the hardest to bring up to band C, a town carrying more of it will show a lower headline efficiency figure even when every individual house type performs identically.
This tracks the national picture exactly. Across the whole EPC register, the share of homes reaching band C climbs with build era: about 19% of pre-1945 homes, 39% of 1945–1982 homes, 56% of 1983–2002 homes, and roughly 93% of homes built from 2003 onwards. Successive tightenings of the Building Regulations — insulation standards, glazing, condensing boilers — did the work. Darlington simply has a larger inheritance of the oldest stock, and the arithmetic follows. The same mechanism drives the wider Teesside and County Durham terrace retrofit picture.
What each home type sells for
The price similarity holds across property types, too. Both towns are led by semi-detached sales by volume, and a detached home fetches an identical median in each.
| Property type | Stockton median (n) | Darlington median (n) |
|---|---|---|
| Detached | £295,000 (957) | £295,000 (466) |
| Semi-detached | £162,250 (1,178) | £169,995 (679) |
| Terraced | £120,000 (666) | £126,500 (450) |
| Flat | £80,000 (105) | £95,000 (111) |
Terraced homes — the band most exposed to the pre-1930 efficiency penalty — are the cheapest houses in both towns, which is where a buyer weighing purchase price against likely running cost and future upgrade work faces the sharpest trade-off. For a sense of how the neighbouring market compares, see the median house price in nearby Middlesbrough.
The wider backdrop
Both towns' prices have edged up rather than fallen over the past year. On the ONS UK House Price Index, smoothed across the three months to April 2026 to strip out month-to-month noise, Stockton-on-Tees was up about 1.7% year on year and Darlington about 2.3%, against roughly 1.6% for England as a whole and 4.1% for the North East region. These are backward-looking measures of what has already happened, not a forecast of where prices go next.
None of the figures above value any individual home — they are medians of what buyers actually paid and the efficiency bands of stock already certified. Council tax bands, for their part, reflect 1991 valuations rather than today's prices, which is why two towns with nearly identical median prices can still differ by around £96 a year at Band D; our explainer on how council tax bands work covers the mechanics.
For a buyer, the practical read is simple: in this corner of the Tees Valley, purchase price and monthly outgoings say little about how warm or cheap-to-run a home will be. The EPC and the build era say far more. You can browse more regional price guides or run any Tees Valley postcode through the tool to see the price, council tax and energy rating for the homes on a specific street.
Based on 4,612 Land Registry standard transactions and 68,568 EPC certificates across the two authorities, plus 2026-27 council tax data (see our other guides). This is general information, not financial, tax or property advice. Speak to a qualified adviser before acting.