I need some help trying to set this up.. what are the best settings? The idea is that we would want to be secure, but not at the expense of not being able to accept transactions from outside of the US... What do you use?

Reject If...
Address information is not provided for AVS Check (B)
AVS Error (E)
Non US Card Issuing Bank (G)
Retry, system is unavailable (R)
AVS is not supported by card issuing bank (S)
Address information for cardholder is unavailable (U)

Reject If Street Address Matches AND
First 5 digits of Zip Code Match (Y)
First 5 digits of ZIP Code Do NOT Match (A)

Reject If Street Address Does Not Match AND
9 digits of Zip Code Match (W)
First 5 digits of Zip Code Match (Z)
First 5 digits of ZIP Code Do NOT Match (N)



Thanks!

These settings have worked best for me, allowing most international orders while blocking blatantly wrong addresses:

Reject If...
Address information is not provided for AVS Check (B)
AVS Error (E)
Retry, system is unavailable (R)
[Reject If Street Address Does Not Match AND ] First 5 digits of ZIP Code Do NOT Match (N)

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I found that checking the street address rejected too many valid orders, and rejecting "AVS is not supported by card issuing bank (S)" blocked many UK and Canadian orders I would like to accept.

AVS alone is simply not enough though... I always also check the IP location (city, state and country) versus the billing address, and do a reverse phone lookup (http://www.reversephonedirectory.com/) on the customer's phone number. Since my orders generally involve a website URL of some sort, I also check WHOIS data to see when the domain was registered and to what address.