| Description | Otley Gas; Oundle Gaslight & Coke; Oxford & District Gas; Padstow & St Columb Gas; Pembroke District Gas; Penicuik & District Gas; Penistone & District Gas; Penryn Gas; Penzance Gas; Peterborough Gas; Petersfield & Selsey Gas; Pickering Gas & Water; Pitlochry New Gas Light; Plymouth & Stonehouse Gas Light & Coke; Pocklington New Gas; Polmont District Gas, Pontardulais Gas |