to vs two

The core difference

Two is a numeral, nothing else. It counts things. To is one of the busiest small words in English: it points towards a destination, and it marks the infinitive form of a verb.

Using each one

• Two (the number): Two of the printers are broken. It takes two hours.
• To (direction or recipient): Post it to the London office. Give the file to Marcus.
• To (before a verb): I need to phone the bank. He forgot to sign it.

The test

Try the digit. 'We booked 2 tickets' reads fine, so two is right. '2 the London office' is gibberish, so it must be to.

That single substitution settles every case, because two has exactly one meaning and it is a quantity.

The memory trick

The number words two, twin, twice and between all carry the same tw. If your word is about a pair, it keeps the W.

Don't forget the third one

The set is really a trio: to, too and two. Too means excessively or also — 'too expensive', 'I'm coming too'. When you are unsure, run both tests: try the digit 2 first, then try swapping in also or excessively. If neither works, the answer is to.

Where confusion actually shows up

Genuine mix-ups are rare in careful writing, but predictive text and fast typing produce them regularly, especially in phrases where a number is plausible: 'to of them' for 'two of them', or 'a two do list' for 'a to-do list'.

A related trap is to versus too in the phrase 'me to' — it should be 'me too'. And in formal writing, numbers under ten are usually spelled out, so 'two weeks' rather than '2 weeks', even though the digit test uses the numeral.