Address Requirements

The tax calculation service requires specific address information be provided in order to properly calculate tax. This section goes over how the tax calculation service uses address information to calculate tax.
There is additional address related information in the US and Canada section that explains specific request fields. See US and Canadian Addresses.

Multiple Shipping Destinations in a Single Order

You cannot specify a different shipping address for each item in an order. When the order contains multiple items that are going to different addresses, you must send a separate tax calculation service request for each shipping address.

Missing Origin Addresses

The destination address is substituted for the origin address when no origin address or a partial origin address is specified. For the best results, use fully validated origin and destination addresses.

Invalid Address Combination Correction

The tax calculation service performs an implicit address validation; if successful, the entire address is used for tax calculation
In case the full address validation failed, engine looks for “Zip + 4” – if it has been provided. If provided, tax is calculated with the “Zip + 4”. If ”Zip + 4” is not provided or is incorrect, engine looks for “City & State” or Zip; if either are provided and are accurate, tax is calculated based on these details. If the zip code does NOT lie within the state, then the city and state are used to determine the region for the tax calculation. Note: In certain cases, Zip alone is not enough to accurately determine the jurisdictions; in such cases, engine looks for additional information – such as Address Lines or City and State. If either is provided and enables identification of the jurisdictions, the successful tax calculation is returned. As Jurisdiction data is in a regular state of change, partial addresses can produce different results over time as the jurisdictions and tax authorities change.
Abbreviations used for some city and county names are acceptable in more than one form. For example, St. Louis is acceptable as 
Saint Louis
St Louis
, and 
St. Louis
. See City Abbreviations.