Ask an expert: 'How do I switch current account without closing my existing account?'

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Q:I want to open a new current account to earn some interest but I really don't want to close my old one. Is it possible to have both and get the benefits?

Submitted via the Which? Money Helpline.

A: If you want to open a new current account and keep your existing one you'll need to do a partial switch rather than a full switch.

However, a partial switch has some limitations compared to the full switch service, especially when it comes to the perks you qualify for, time it takes and guarantees if things go wrong.

Partial switch service vs. full switch service

The full switch service, known as the Current Account Switch Service (CASS), automatically transfers standing orders, directs debits, bills and income like your salary or pension to a new bank account and closes your old one within seven days.

It also comes with a guarantee which ensures payments are redirected from the closed account and if anything goes wrong you will be refunded any charges or interest.

The partial switch service is similar to the Current Account Switch Service, but won't close your old account or automatically transfer payment arrangements and isn't restricted to a seven-day time scale. It's also not covered by the guarantee so payments aren't redirected and there's no redress if anything goes wrong.

Here's a summary of how the two services differ:

Source: BACS

Is a full or partial switch right for you?

The partial switch service is useful if the bank or building society you're moving to isn't a member of the CASS scheme (only around 40 are) or if you don't want to close your old account.

But many of the most enticing current account deals specify that you must use the full switch (CASS) service to benefit from key incentives like a cash bonus.

Clydesdale and Yorkshire Banks, for example, recently launched 'A Big Hello' £250 offer (the biggest we've ever seen) to encourage people to move to their accounts.

However, the offer came with a long list of caveats including the requirement to use the full switch service (CASS) that transfers all payments and closes your old account.

That said, not all current providers are that strict and you may be able to use the partial switching service if you want to keep your old account open and benefit from more long-term benefits like in-credit interest and cashback.

• Use our comparison tables to see the best high-interest current accounts

How many people do partial switches?

In the grand scheme of things, partial switching represents quite a low proportion (3.6%) of overall current account switching numbers.

The latest current account switching figures provided by BACS, show there were over 24,000 partial current account switches between January and September this year, compared to nearly 660,000 full switches.

Having more than one current account is a savvy move if, say you want to take advantage of the raft of high interest deals on the market right now.

This isn't as simple as it sounds though. Most providers have a variety of hoops you need to jump through to qualify for the benefits of an account like minimum monthly deposits and having a certain number of active direct debits.

It's possible to juggle these requirements and benefit from more than one account with a little effort. Watch our video on how to play the high-interest current account game for more.

Best accounts for partial switchers

We've rounded up some of the top current accounts that allow you to do a partial switch and still benefit from their main perks. The list is in alphabetical order.

Currently, the cash incentives available on the Halifax (£125), First Direct (£100), HSBC (£200) and M&S Bank (£185) current accounts require you to perform a full switch to benefit. However, the banks all do offer a partial switch services if there are other perks on the accounts that you're interested in.