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Past tense of “cost”

💰 To have a particular price.

Number 37 of 175 by frequency, well inside the everyday core, and all three forms are the same word. Worth learning properly rather than recognising vaguely.

Phrases you will actually hear

These are worth learning whole. A verb sticks far better inside a phrase somebody would really say than on its own in a table.

One word doing three jobs

Nothing changes. cost is the base form, the past simple and the past participle, which sounds like a gift until you notice the catch: the word itself no longer tells you what time you are talking about. Only the rest of the sentence does.

I cost it every day · I cost it yesterday · I have cost it before — identical verb, three different times. Learners often reach for costed to make the past feel like a past. It is not a word.

Most verbs in this group already end in -t or -d, which is roughly where the -ed ending would have landed anyway. English simply stopped bothering.

The same pattern — one form fits all — runs through 22 verbs: