Referral schemes are all the rage and you could be quids in, simply by recommending products and providers to people you know.
Here are some of the latest offers you might be able to take advantage of.
Nationwide is offering a referral bonus to existing FlexAccount, FlexDirect or FlexPlus customers that recommend a friend or family member to sign up.
If that person switches their main account to Nationwide using the Current Account Switch Service, both sides receive £50.
Nationwide will allow up to ten referrals every 12 months, meaning it's possible to earn up to £500 a year through the scheme. However, this is being doubled during July, so you will receive £100 for each referral.
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A number of credit card providers also offer rewards for referrals.
Tesco Bank, for example, has a refer-a-friend scheme for its Clubcard Credit Card holders. Existing customers can earn 1,000 extra Clubcard points (worth £10) for themselves and the person they introduce when they're approved for a card. You can refer as many friends as you like.
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Savings and investments
People using peer-peer platform Funding Circle can net £50 if they recommend a friend or relative who goes on to lend at least £1,000. Meanwhile Zopa customers can earn up to £50 if the person they recommend lends £2,000 with the platform. They'll receive £50 too.
Elsewhere Alliance Trust Savings will give existing customers a £50 Marks and Spencer when they get a friend or family member to open an Investment Dealing Account, ISA or Select SIPP. Your friend will get £25 worth of vouchers, too.
Mutual Scottish Friendly is offering £25 MyRewards card or top-up to their customers and anyone they recommend that takes out a plan or policy.
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Some mortgage providers also have schemes in place to encourage existing customers to recommend them to people they know.
Leeds Building Society, for example, is offering existing members the chance to earn a £50 bonus for referring up to four friends or relatives for a mortgage. Those that take out a deal will also get a cheque for £50.
Newcastle Building Society is offering £100-worth of M&S vouchers to existing members who recommend a friend that goes on to take out a mortgage. The friend is also rewarded for signing up with a £50 M&S voucher.
Cashback websites are also using cash incentives to encourage people to spread the word.
Quidco is offering a £2.50 cashback bonus when members recommend the site to someone they know. The scheme works through sharing a personalised referral link in an email or via social media. Once someone the referrer knows uses the link to sign up and earns at least £5 cashback they'll receive the bonus.
Rival TopCashback also operates a referral scheme. It offers £10 cashback (jumping to £15 for Plus members) for each person a member introduces. Again members just need to share a personalised referral link through email or via social media. Once someone they know signs up using the link and earns at least £10 cashback they'll receive the bonus. Their friend will also pocket a £5 Amazon voucher.
TV, broadband and phone
One area where recommending friends is particularly popular is the broadband market.
Some are offering discounts on bills.
Plusnet, for example, runs a referral scheme, which gives broadband and phone customers a monthly discount for every person who joins following their recommendation. It varies on the product they sign up for, but is normally 50p or 75p off their bill for each month the friend stays on as a customer.
Elsewhere Virgin Media offers a £50 bill discount to existing customers that refer a friend to its broadband and TV service. If that person signs up they also get a £50 bill discount.
Other providers are offering vouchers to encourage customers to spread the word.
The Co-operative Phone and Broadband is offering referrers £20 credit for every one that becomes a customer. They'll bag a cool £20 in credit, too.
Fuel Broadband is offering a deal when existing customers recommend one of its broadband plans. If the referral leads to a sign up, both get a £25 Amazon voucher.
Sky TV customers that recommend a friend will get a high street voucher or prepaid MasterCard worth £75 for themselves and the person they introduce.
Gas and electricity
You could also earn a reward by recommending your energy company.
Ovo Energy is offering a £25 John Lewis voucher to both referrer and friend.
Elsewhere Utility Warehouse, which provides gas and electricity tariffs as well as other utilities, also uses a referral scheme. Members can get up to £150-worth of shopping vouchers on a tiered basis; £10 for the first friend introduced, £20 for the second and so on up to £50 for the fifth friend that joins.
As well as the voucher when they join, members also get a £10 voucher every Christmas for every friend who has been a customer for at least four months.
Ocado has an Invite a Friend scheme which offers £20 for the referrer and every person they get to join up.
Unique furniture website Made.com is offering a £15 voucher for the referrer and every friend they recommend.
You can even earn money through referring friends for cosmetic procedures.
Laser eye surgery clinic Optimax for example pays £50 for every friend or relative you get to have treatment while they get £250 off the procedure.
Meanwhile Harley Medical Group, which provides a range of cosmetic treatments, offers a £100 cash incentive to recommend a friend or the option of £200 off your next treatment as a thank you.
In some industries referring your friends for jobs can also result in a cash payment.
For example, Corecruitment, which operates in the service industry, pays up to £500 for every recommendation that results in someone being placed in a position and staying there at least three months.
When it comes to jobs it's best to check out what your company offers if you recommend a friend for a position – but remember it might reflect badly on you if things don't work out well after they're offered a job!
If you don't have many friends or at least don't have enough who are in the market for a new broadband provider or bank account there's a website that offers to pair up referrers and "friends".
Refer Me Happy lists the latest referral schemes from various companies. Top deals on the site at the moment include Sky, Virgin Media, Ocado, Three Mobile, Next and Betfair.
There's undoubtedly money to be made from these schemes, but are they a good idea?
In general, when it comes to current accounts, mortgages and credit cards, what's best for one customer might not be ideal for another.
Essentially, before signing up to a contract for any type of service, it's a wise move to shop around and be sure the product is right for you, rather than being swayed by incentives or a friend's recommendation.
Referral offers also come with a number of terms and conditions. Inevitably most only pay out if your friend actually buys, rather than just enquires about, the service in question.
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