See also the Address response object.

The only attribute required to create an address is the customer_id. Addresses stored in the Vault need to be associated to a customer. You can't specify Address ID. It is always generated by the gateway as two alphanumeric characters. Address IDs are unique to the customer, so multiple customers can have the same address ID.

There is a limit of 50 addresses that can be saved per customer. Addresses can also be created with a payment method or created with a customer and a payment method.

Ruby 
result = gateway.address.create(
  :customer_id         => '131866',
  :first_name          => 'Jenna',
  :last_name           => 'Smith',
  :company             => 'Braintree',
  :street_address      => '1 E Main St',
  :extended_address    => 'Suite 403',
  :locality            => 'Chicago',
  :region              => 'Illinois',
  :postal_code         => '60622',
  :country_code_alpha2 => 'US'
)

If the customer can't be found, it will raise a Braintree::NotFoundError.

Parameters
:company String

Company name. 255 character maximum.
:country_code_alpha2 String

The ISO 3166-1 alpha-2 country code specified in an address. The gateway only accepts specific alpha-2 values.
:country_code_alpha3 String

The ISO 3166-1 alpha-3 country code specified in an address. The gateway only accepts specific alpha-3 values.
:country_code_numeric String

The ISO 3166-1 numeric country code specified in an address. The gateway only accepts specific numeric values.
:country_name String

The country name specified in an address. We only accept specific country names.
:customer_id required, String

A string value representing an existing customer in your Vault that you want to create an address for.
:extended_address String

The extended address information—such as apartment or suite number. 255 character maximum.
:first_name String

The first name. The first name value must be less than or equal to 255 characters.
:last_name String

The last name. The last name value must be less than or equal to 255 characters.
:locality String

The locality/city. 255 character maximum.
:postal_code String

The postal code. Postal code must be a string of 4-9 alphanumeric characters, optionally separated by a dash or a space. Spaces and hyphens are ignored.
:region String

The state or province. For PayPal addresses, the region must meet PayPal's state restrictions; for all other payment methods, it must be less than or equal to 255 characters.
:street_address String

The street address. 255 character maximum. Required when used to create payment methods or transactions that perform verification when AVS rules are configured to require street address.