Tax return advice - reducing the on account payment

[Liveinthepresent]

Can anyone help with this?
DH is on an interim contract and so self employed.
In the early days he wasn't so clued up on how the system worked - so although we have set aside the amount for the retrospective figure - he wants to spread out the on account payments and not have to pay 50% now.
Does anyone know what the criteria are for HMRC accepting this ?
Has anyone else done this successfully?
TIA

www.gov.uk/understand-self-assessment-bill/payments-on-account

I'm not sure if you can do this, and if you can then you'd have to pay interest at a rate that will certainly be higher than what he can get from a savings account. Remember that money you earn up to April of a certain year doesn't have to have the tax paid until January of the following year, so you have a while to save it.

Thanks for the reply - we spoke to a family friend accountant who said just to offer what we were happy to pay up front and that as long as its a reasonable chunk it will probably not we questioned. There is interest but not enough to worry about compared to the cash flow pressure of paying 50% of the tax that is due next January now.
We have paid the April 13 - 2014bill in full - this is just the on account bit.
Setting it aside so that we will be fully up to date with tax and have minimal Extra tax Billayable Jan 16