I know this is an old thread, but as I found it when searching for the same thing, I thought I would offer what worked for me.

Quick Books Online of course, so hit the GEAR on the top right.

From there click on ALL LISTS at the top of the Lists heading.

That brings to you the Lists page and you will see PAYMENT METHODS as one of the options. Click that.

Now you are brought to that list of items you see when you Record Money. Cash, Check, Credit, E-Check, etc. To the right of all of these is a down arrow and when clicked a small sub menu appears with 2 options Edit and Make Inactive. Select EDIT.

That brings up a pop-up window that says EDIT PAYMENT METHOD and has the name of the item you chose, (for example CREDIT). Under that is a line that reads THIS IS A CREDIT OR DEBIT CARD and there is a check box. CLEAR that check box and hit SAVE at the bottom.

Repeat this for every item you want (which is probably all items if you are here reading this). Once you are done, when you return to the Record Payment screen, you will no longer even have a check box below to check or uncheck. This removes that option entirely (which as far as I'm concerned is great!)

NOTE: When I first went to check after doing this, I found that it did not work. That seems to be because Online is slow to update stuff sometimes. I went to take care of a couple of other things, and when I returned maybe 3 or 4 minutes later to the Record Payment screen it was like I described above and no longer there. So give it a few minutes if the above doesn't work right away. Or even log off and log back in so the settings take hold. But it did work for me at least as of July 22, 2025 when I wrote this. Who knows what other 'features' they may add to break this functionality in the future, but for now it works.