I've put together the below spreadsheet to compare First Direct's Cash e-ISA with their Regular Saver ISA.
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The two scenarios depicted are:
Regular Saver ISA (7% AER)
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User deposits the maximum of £300, every month, for 12 months. Cash e-ISA (5.53% AER)
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User deposits one-off maximum of 3300 on first day, and then deposits nothing further for 12 months. Can someone please advise if I've lain out the interest correctly?
It looks to me that the Regular Saver ISA loses (although I suppose the money that is not deposited at the outset can be earning elsewhere.)