Can I use cash from other HL accounts to make a SIPP contribution?
Yes, if you have money available in a Fund & Share Account or Loyalty Bonus Account you can contribute this to your HL SIPP subject to the usual pension contribution limits.
Please note, once the cash has been transferred to your HL SIPP, you usually can't access it until you reach the minimum retirement age, currently 55 (57 from 2028).
Once you've logged in to your account, simply go to the account which contains the cash you wish to transfer and follow the instructions to transfer money.