Variation to invoice issued by subcontractor

PAMDILL

Help!!

I work in Construciton industry, as you know times are tight here, following scenario has arisen and I want to keep on the right side of HMRC.

(Never good idea to do otherwise)

We have requested a 2.5% discount from a couple of sub-contractors who have already issued us with VAT invoices.

They are refusing to do so, my boss has insisted that I send them a variation to contract with their payment showing we have taken this.

Apparently some other contractors are doing this for 20% deductions and they are sending them out like a VAT self billing invoice (only as a credit note)

Should I do the same and enter it through my ledger as a VAT credit note or should I just do a deduction from their ledger account as discount taken without a VAT element?

Any suggestions welcome.

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