US Sales and Use Tax - Extended Jurisdictions not loaded in Oracle, wrong tax rate applied in AR

Summary:

Extended Jurisdictions don't exist in Oracle, wrong county tax rate applied in AR

Content (required):

Using Vertex Oramast file to load tax detail. For Colorado - Arapahoe County - three possible rates can apply for Aurora. Vertex data contains only one jurisdiction code and has advised that county has 'extended jurisdictions' with different county rates that are not loaded to Oracle therefore tax gets applied to Receivables invoices at the incorrect rate and another jurisdiction code with the correct rates cannot be selected because it doesn't exist in Oracle. How do other companies deal with this situation?

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