npower in a nutshell

  • npower is the third-largest electricity and gas supplier in the UK.
  • npower is one of the UK's largest generators of electricity.
  • It is the most expensive energy supplier of the Big Six but has the longest fixed-price tariff.
  • npower customer care has a flaky reputation.

npower, the youngest of the Big Six

Originally founded as Innogy in 2000, npower as we know it was founded in 2002 when the German energy giant RWE acquired Innogy and rebranded the company.

npower corporate facts

Led by CEO Paul Massara, npower employs 11,500 people. The company supplies electricity and gas to around 6.5 million residential and business customers and produces roughly 10% of the electricity used in Great Britain. In 2012, npower made £6.8 billion in revenue.

npower's vertical integration of electricity generation and supply

Although contrary to its peers of the Big Six, npower has little interest in gas production and storage, the company accounts for over 13% of the electricity generation capacity in the United Kingdom:

  • 1,586 MW of this generation capacity comes from coal-fired power plants.
  • 6,474 MW comes from combined cycle gas turbines.
  • 1,370 MW comes from oil-fired power plants.
  • 324 MW comes from wind and hydro power plants.

Over half of the npower fuel mix is natural gas

The following chart gives the components of npower’s fuel mix, which relies mostly on natural gas, followed by coal and renewable energy (where npower scores well compared to all other Big Six energy suppliers, save SSE).

Current npower energy prices

To give you an idea of npower prices, here are npower average annual energy costs per tariff as of May 2014 for the UK (based on an annual usage of 3,200 kWh for electricity and 13,500 kWh for gas). It is interesting to note that none of npower’s tariffs have early exit fees. However, compared to the other Big Six electricity and gas suppliers, npower appears to be one of the most expensive for standard comparisons.



Average cost duel fuel


- Variable tariffs
- No contract end date or renewal

£ 1,206

Online Price Fix April 2016

- Fixed electricity and gas rates until 30 April 2016
- Online account management only

£ 1,164

Price Protector Sept. 2016

- Fixed electricity and gas rates until
30 September 2016

£ 1,186

Intelligent Fix April 2017

- Fixed electricity and gas rates until
30 April 2017

£ 1,218

Contacting npower

Contacting npower by telephone

Like most Big Six energy suppliers, npower customer service operating hours are quite long, except for the complaints line.


Contact numbers

Operating hours

Account and general enquiries

0800 073 3000 (landlines)
0330 100 3000 (mobiles)

Mon-Fri, 8am-8pm; Sat, 8am-6pm

Moving home

0800 316 8558 (landlines)
0330 100 8658 (mobiles)

Mon-Fri, 8am-8pm; Sat, 8am-6pm


0800 316 9328 (landlines)
0330 100 8628 (mobiles)
0845 155 0060 (boilers and heating)

Mon-Fri, 8am-6pm; Sat, 8am-2pm

Switching to npower

0808 156 0056

Mon-Fri, 8am-8pm; Sat, 8am-6pm

National Gas Service Emergency Line

0800 111 999


Contacting npower by mail

You can send letters to npower to:
Customer Relations
PO Box 97
County Durham

npower customer reviews

npower complaints performance

From January to March 2014, npower received 450,178 complaints, of which 384,577 were resolved within one working day (85.4%). Most complaints addressed to npower are about billing (70%). The remaining complaints regard payments (10%), metering (6%), energy supplier transfers (9%) and debt (2%). Of the Big Six electricity and gas suppliers, npower receives the most complaints by far. However, it is relatively efficient in resolving them within one working day.

What customers say about npower

Selected positive reviews about npower

  • npower calls customers back

“Being able to leave your number to customer care for them to call you back is convenient if you don’t feel like waiting on the phone.”

  • npower supports employment in the UK

“All npower call centres are in the UK, which creates jobs and is something positive in the current economic climate.”

  • npower has convenient free text alerts

“I have an online account with npower and I appreciate the free text alert system since I don’t always have time to monitor my account regularly.”

Selected negative reviews about npower

  • Suboptimal npower customer service

“I found npower customer care disappointing: it feels as though people don’t communicate and you have to explain billing issues over and over before they get dealt with - it’s frustrating.”

  • Lengthy npower account transfers

“Moving home and staying with npower was very disorganised. A four-month process involved missing bills, technical difficulties with my online account and varying debit amounts. Not impressed.”

  • npower payment issues

“Though I’ve authorised direct debit, I keep being invoiced for quarterly debits on my electricity and gas accounts with npower.”