How to Easily Change Tax Details in Microsoft Dynamics GP
Governments change their sales tax rates periodically and when they do they tend to make the tax rate effective on a specific date. The challenge is how to update your system correctly for this change.
You can easily change your tax details in Microsoft Dynamics GP by going to Administration > Setup > Company > Tax Details. You may need a user that has Administrative privileges to do this for you if your user ID is not configured to do so. In that case you may not even see this as a menu option. Select the affected tax details and change the Percentage field to the new %. Save your changes.
Note that you will not have to make any change to the Tax Schedules because the tax schedules that are entered on transactions use the settings from the tax details.
In this example below, I have changed a tax detail used on Manitoba sales to 7.00000%.

Pretty straight forward to get here, but now we need to deal with the existing orders and invoices already in the system. The change above will affect all future entries to Dynamics GP for Sales Orders and Purchases transactions. The rate is correct on the shipped orders but the unshipped orders will be incorrect as they have been stamped with the old tax rate. Each order will need to be recalculated to force an application of the new rate for them to be correct so they ship under the new tax rate.
We have two ways to correct this:
Manually
If there are a few orders (up to about 20-50 orders) and you only ship to one customer, ship to the address per order, then the fastest and cheapest way is to allow GP to recalculate the order lines with the new tax. This is done by:
1. Opening sales transaction entry.
2. Selecting the order.
3. Select the Ship to Address on the main screen.

4. Press CTRL-X (this removes the ship to address from the header).
5. Press Tab to leave the field.
6. A question will appear to roll down the changes.
a. Select yes.
b. This will wipe out the current taxes on the document.

7. Click back on the Ship to address.
8. CRTL-V (restores the ship to address to the header).
9. The question will reappear to roll down the changes.
a. Select yes.
b. This will re add the new tax to all line items.
10. Repeat for all unshipped documents.

Programmatically
If there are too many documents to do then Encore has software that can change them en masse. Please contact Encore for costing and availability. This is only required when the taxing authority changes its rate.
If you have any questions about your Dynamics GP solution, please get in touch with us.
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