The trickiest part of English numbers isn't counting to ten — it's hearing the difference between thirteen and thirty. The rule that rescues you: the -teen numbers (13, 14, 15…) stress the end, so you say "thir-TEEN," while the -ty numbers (30, 40, 50…) stress the start, so you say "THIR-ty."
Even native speakers mishear these, so they lean on a simple habit — they confirm the digits. This guide covers that famous trap, plus the number habits that quietly trip learners up: ordinals, big numbers, prices, and dates.
Thirteen or thirty? The listening trap
The confusing pairs are 13/30, 14/40, 15/50, 16/60, 17/70, 18/80, and 19/90. On paper they're clear. Out loud — on a noisy phone line or a busy street — they blur together.
Two things separate them. First, the stress: "thirteen" puts the beat on the second half, while "thirty" puts it on the first. Second, the ending: the -teen words finish with an n sound, and the -ty words don't.
When the number matters — a price, a room, a train platform — do exactly what natives do and check digit by digit: "Sorry, is that one-three or three-zero?" Nobody finds this rude. It's the normal English rescue move.
Ordinals: first, second, third, and the -th family
Counting words (one, two, three) are cardinal numbers. The order words (first, second, third) are ordinal numbers, and English uses them for dates, floors, and rankings.
The first three are irregular. After that, most numbers just add -th.
| Number | Ordinal |
|---|---|
| 1 | first |
| 2 | second |
| 3 | third |
| 4 | fourth |
| 5 | fifth |
| 20 | twentieth |
| 21 | twenty-first |
In American English, spoken dates use ordinals: you write "June 1" but say "June first." The numbers and counting guide walks through the full set.
Big numbers, prices, and phone numbers
Read long numbers in the groups the commas mark. 1,500 has two equally natural readings: "one thousand five hundred" or "fifteen hundred." Both are common; the shorter one feels a little more casual.
Prices usually drop the words "dollars" and "cents." $19.99 is said "nineteen ninety-nine," not "nineteen dollars and ninety-nine cents."
Phone numbers are read digit by digit, in small groups. The digit 0 is read as "oh" or "zero." In the UK, a repeated digit gets bundled: 55 becomes "double five."
| You see | You say |
|---|---|
| $19.99 | nineteen ninety-nine |
| 1,500 | fifteen hundred |
| 555-0182 | five-five-five, oh-one-eight-two |
| 55 (UK) | double five |
Dates: the format that causes real confusion
This one genuinely matters, because it causes mistakes with flights, forms, and meetings.
6/1 means June 1 in the US (month first) but 1 June in the UK (day first). When a date could be misread, spell the month out — "6 January 2026" — and the confusion disappears. Airlines and hotels watch travelers get this wrong all the time.
Saying the year has two styles too. 2026 is usually "twenty twenty-six," while a year like 2005 is more often "two thousand five."
Keep learning English
Numbers reward a little drilling, because in real life they arrive fast — prices at the till, gate numbers, a phone number said only once. Practice saying them out loud with audio in the Pretalk app, and build the foundation with our free English grammar guides so the teen/ty pairs stop tripping you up.
