Overview
Natural gas (mains gas) and LPG (liquefied petroleum gas) are both used in standard boilers — in fact, most boiler models can run on either with different burner jets fitted. The differences are in fuel cost, storage, and supply logistics.
Fuel cost comparison
Natural gas: approximately 6p/kWh. LPG: approximately 8–10p/kWh. LPG is typically 35–65% more expensive per unit of energy. For a typical UK home using £1,000/year in natural gas, LPG equivalent heating cost would be £1,350–£1,650/year.
Storage
LPG requires a bulk storage tank (typically 1,000–2,000 litre), either owned or rented from the supplier. This requires suitable outdoor space and planning permission in some cases. Natural gas: no storage needed — piped continuously.
Supply security
LPG: tank must be monitored and refilled (typically 2–4 times per year for heating). Running out of LPG in winter is a real risk — smart tank monitors help. Natural gas: continuous supply, no stock-out risk.
Installation cost
LPG boiler installation: similar to gas (£999–£1,499 for the boiler). Plus tank installation if not already present: £500–£1,500. Natural gas: no tank needed.
Efficiency
Both achieve similar efficiency ratings — modern condensing LPG and gas boilers are both 89–94% efficient. Effectively equal.
Verdict
If your property has a mains gas connection, always use natural gas — cheaper, simpler, no storage concerns. LPG is the right choice for off-grid properties where oil is the only alternative and LPG is preferable (cleaner, no filter required, easier to handle).