Correct opposite of checkbox ticked

I want to write "If left unticked ......" , but it seems like unticked is not a word(or is it?), what would the correct opposite of ticked because I use "If ticked ...." at the beginning of paragraph.

Solution 1:

The word “unticked” is found defined in the Cambridge Dictionary but not in the Merriam-Webster online dictionary. It is not used in American English and the equivalent word is “unchecked”.

Normally you would say either,

I left the tick box unticked. BRITISH

OR

I left the checkbox unchecked. AMERICAN

It may be regarded as strange by many native English speakers to mix the different usages.

However, in Australian English “tick” is preferred but “check” is very possible too particularly in “checkbox” as it’s what these boxes are labelled on websites and in popular spreadsheet applications. So, “Leave the checkbox unticked” sounds like perfectly acceptable English to me.

Solution 2:

"unticked" is a valid adjective.

"Accounting: A Practical Approach" Valarie Wilson, ‎Suellen Freeman, ‎John Freeman - 2015 - Page 295:

b Unticked items in the cash payments journal or cash book represent unpresented cheques...