Thank you for reaching out and posting this question!
There are a few other third-party gateways available in the UK, such as Klarna or Laybuy, that does allow your customers to finance or pay installments with zero interest. However, I'm not sure if they allow 0% APR over 12 months, so I'd recommend reaching out to them directly for further inquiries. If neither of these can offer what you're looking for, then you can take a look at our complete list of supported payment gateways in the UK.
I'd love to know if Klarna or Laybuy can help you achieve what you're looking for. Keep me posted!
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