Hi TWaye, possible you can setup 2 tax code, i.e. H3 for 15% and H5 for 15%?

There are a number of ways to do this but none are really more right than wrong. It's all up to personal preference.

I personally wait to change my main tax code (eg. H) rate until I am finished my customer billing for the month. Then I will change it to do my billing for the new and future months. For all subsequent vendor invoices that are dated before July, on each line of the purchase invoice, I hit Ctrl-Y and change the dollars to the correct amount.

All invoices I need to adjust that were posted before I changed the rate will continue to have the old rate for the same tax code and the new rate will not be available. For new invoices posted after the change in rate, the old rate will not be available for the same tax code H, even if I have to adjust them. The changes to tax code rates are date sensitive to the date of change, not the effective date of use.

Because you have changed the rate already, you can add a new tax code for the old rate and use it on the customer invoices dated before July. This will make sure any customer invoice will have the appropriate description for the tax code on the invoice.

Some people will just create a new code for the new rate and leave the old code alone. Personally I don't like this because Sage will only give us two characters for a tax code so you can't put the full rate in the name. But some people add one with H5 for 15% instead of H3 for 13%.