Cardinal Numbers 100 and Beyond

Once you can count to 100, scaling up to the thousands and millions is mostly pattern recognition — with a few stubborn irregularities and one rule about gender agreement that English speakers often miss.

Cien versus ciento

This distinction was introduced in Cardinal Numbers 31–100 but it's worth reinforcing here because it keeps coming up.

• cien — used for exactly 100, and also before mil and millón.
• ciento — used when 100 is followed by a smaller number (101–199).

The hundreds: 200 to 900

The hundreds are mostly formed by combining a digit with -cientos. Three of them are irregular and must be memorized.

Watch out for quinientos (not cincocientos), setecientos (not sietecientos), and novecientos (not nuevecientos). These three are the main irregularities — everything else follows the pattern.

Gender agreement in the hundreds

Unlike English, Spanish hundreds agree in gender with the noun they count. If the noun is feminine, change the final -os to -as.

Mil: one thousand

The word for 1000 is simply mil. Unlike English, Spanish does not say "un mil" — you just say mil. The plural miles exists but means "thousands" in a vague sense ("miles de personas" = thousands of people), not a specific count.

Notice that there is no y between mil and the hundreds. Spanish uses y only between tens and units. So 2,350 is dos mil trescientos cincuenta — no y after mil.

Un millón and the de rule

One million is un millón. Unlike mil, you must include un: it's un millón, never just millón. The plural is millones, with the accent dropped (millón → millones).

When millón or millones is followed directly by a noun, you need de.

However, when another number sits between millón and the noun, the de disappears: tres millones quinientos mil pesos (three million five hundred thousand pesos).

Large numbers in writing

In Latin American Spanish, large numbers are usually written with a comma as the decimal separator and a period or space as the thousands separator — the opposite of English.

Reading large numbers aloud

To read a long number like 1.234.567 in Spanish, break it into pieces the same way English does, but using millones and mil as dividers. The number above reads as un millón doscientos treinta y cuatro mil quinientos sesenta y siete.

Notice that mil is invariable — it never becomes miles when used as a multiplier ("three thousand" is tres mil, never tres miles). The plural miles only appears in the vague expression miles de... ("thousands of...").

Now that you can handle large quantities, explore how numbers behave in math expressions and measurements.