Question:

I have 1 paid account now, I want to setup an additional filtering account.
This link http://mail.spamcop.net/pricing.php states that it is half-price.

How do I sign up for a discounted account? Or, how do I ask someone to create it?

Answer:
1. Pay the full price for the new account and use the normal procedure.
2. Email support[at]spamcop.net the old and new accountname(+domain) and ask them to be combined into one account.
3. The accounts are combined, the discount is calculated through editing both expiration dates.

as provided by user localhost <== thanks>