Go to the customer ledger where you set up the customer originally, then select the Taxes tab and set the default tax code in the drop down list.

yes the tax code is set up in the customer, the problem is it only shows up on one line on the invoice automatically. we are in the middle of a CRA audit for HST and they found invoices where the person creating invoices forgot to put the H in each line of the invoice, therefore the customer was not charged proper amount of HST. If SAGE would put the tax code automatically at each line where $ are entered then there wouldn't be any "human error"

In my sample 2023.1 file, I have a customer with the default sales tax code and default revenue account set up.

I then start an invoice for that customer and click on the first line in the Amount field.  I can then type 500 and hit enter and repeat 10 times and the default sales tax code and default revenue account will show up on every line.

I then go to the next line where nothing is on the line, enter an item code from the list and it automatically enters the Unit, Description, price sales tax code and the revenue account/department for that item code, not the default revenue account.

Even without the revenue account on the customer ledger, I can enter 500 in the amount column, tab twice, type 4 and hit Enter twice and keep going to do the data entry and the sales tax code shows up.

I don't know why your file has a different behaviour.

thank you so much!!