The word, "Costs" is singular or plural?

I googled the word "costs". with "is" and "was" like "Costs is" and "Cost was". I get tons of results and seems some people use costs as if it is singular, but this word has "s". Is this word singular or plural? Please give me your thoughts. Thank... show more I googled the word "costs". with "is" and "was" like "Costs is" and "Cost was".
I get tons of results and seems some people use costs as if it is singular, but this word has "s".
Is this word singular or plural? Please give me your thoughts.
Thank you in advance.
4 answers 4