Isas: five best cash Isas The only downside is that this rate includes a 2.8pc bonus, again payable for 12 months, so make sure you transfer your money again at the end of this period. 3 Best for long-term fixes If you can afford to lock your money away for longer, you should get a better rate of return on it. Halifax is currently leading the way when it comes to fixed-term Isas. Its five-year fixed rate Isa is paying 4.5pc, while it also offers the best three-year fix, paying 4.25pc. However, those taking up this option must remember that they will pay substantial penalties should they need to access their money before the end of the term. On the five-year deal they will lose a year's interest, while on the three-year bond the penalty will be equivalent to 270 days' interest. 4 Best for short-term fix In the Isa market, one-year bonds have proved popular. These lock your money away for the short-term, but give you the flexibility to either access this money, or move it into another Isa holding at the end of the 12-month period. Currently the best one-year deal is from Saga, paying 3.6pc, but this account is only available to those aged 50 or older. For younger savers, the next best deal is from Marks & Spencer Money, paying 3.25pc - although this pays less interest than the Santander Direct Isa, which also offers instant access. 5 Best Junior Isa For the first time those aged under 18 can take out an Isa in their own name. However, not all children can benefit. Those born between September 2002 and January 2 2011 won't be able to open one of these accounts because they would have already qualified for a Child Trust Fund. Children also can't save as much into an Isa as their parents, the maximum is £3,600. And unlike an adult Isa there isn't the option of accessing this money, at least not until the child's 18th birthday. But it is possible to transfer these accounts, if you find the deal you have taken no longer proves competitive. Nationwide Building Society offers the most competitive cash Isa deal paying 3.25pc. This includes a 1.15pc bonus, payable until January 31 2014.