You blocked "free". You can still pay for "freebies".

You added "free" as a negative keyword months ago. Done, right? Not quite. Someone can search "freebies" tomorrow, see your ad, click it, and you pay for it.

Here's why. Your positive keywords stretch to close variants. Your negative keywords don't.

Google's own help page says it plainly: negatives "won't match to close variants or other expansions." Their example: a negative broad match "flowers" blocks "red flowers" but not "red flower".

So with only "free" on your list, these can still trigger your ads:

• "freebies"
• "jobs" (if you only blocked "job")
• "cheapest" (if you only blocked "cheap")

The 2-minute fix: open your negative keyword list and, for each term, add:

• the singular and the plural
• any obvious synonyms

You can skip casing and misspellings, because Google already handles those.

Then check your search terms report once a week. That's where these leaks show up first.

Source: Google Ads Help, About negative keywords

If you'd like a second pair of eyes, JunkTerms gives you a free analysis of your search terms CSV, and it flags variants like these for you: junkterms.com/demo