Mastering -tion and -sion: The Endings That Trip Up Almost Every Learner

Knowing how to pronounce -tion and -sion endings in English will immediately make hundreds of words clearer — words like decision, production, occasion, and tension that appear constantly in professional and everyday speech. The good news is that these endings follow a small set of reliable rules. Once you internalise them, you stop thinking about each word individually and start hearing the pattern everywhere.

This guide explains exactly what sound each ending makes, when it changes, and how to place the stress correctly. There are worked examples throughout, and a short drill at the end you can do aloud right now.

Why These Endings Cause Trouble#

Both endings are written with letters that, taken literally, suggest very different sounds. Learners who speak Romance languages often try to say "tee-on" for -tion, because that is roughly how the equivalent ending sounds in Spanish, Italian, or French. Learners from many Asian language backgrounds sometimes say "shee-on" or add a clear vowel between the letters. Neither sounds natural to an English ear.

The reason is historical. In Middle English, the -tion ending was indeed pronounced more as it looks. Over several centuries the sounds merged into a single consonant cluster, and English spelling simply never caught up. Today the letter sequence t-i-o-n represents the sound /ʃən/ — the same sh you hear in ship, followed by a short, unstressed uh vowel.

The Core Rule for -tion#

-tion is almost always pronounced /ʃən/ — rhyming with the end of "fashion".

Say these words aloud and listen for that single sh sound followed by a quiet -un:

• nation → NAY-shun
• action → AK-shun
• production → pruh-DUK-shun
• communication → kuh-myoo-nih-KAY-shun

In every one of those words, the -tion ending is identical. The only thing that changes is the syllable before it.

The -stion Exception#

There is one consistent exception within the -tion family. When the ending is spelled -stion, it sounds like /tʃən/ — a ch sound, as in church.

• question → KWES-chun
• combustion → kum-BUS-chun
• digestion → dy-JES-chun
• suggestion → suh-JES-chun

If you have been saying "kwes-tee-on" or "kwes-shun", neither is quite right. The correct sound sits between them: KWES-chun.

The Two Sounds of -sion#

The ending -sion is slightly more interesting because it has two distinct pronunciations depending on what comes before it.

Sound 1: /ʒən/ — the "zh" sound, as in "measure"#

When -sion follows a vowel or the letter r, it produces the voiced sound /ʒən/. This is the softer, more buzzing sound that many learners find unfamiliar, because /ʒ/ does not exist in many languages.

To find this sound, say the word measure or television. The middle consonant — the one that sounds somewhere between a z and a j — is /ʒ/.

Words where -sion follows a vowel:

• vision → VIZH-un
• occasion → uh-KAY-zhun
• decision → dih-SIZHun
• explosion → ik-SPLOH-zhun
• television → tel-ih-VIZH-un

Words where -sion follows r:

• version → VER-zhun
• excursion → ik-SKER-zhun
• diversion → dy-VER-zhun

Sound 2: /ʃən/ — the same "sh" sound as -tion#

When -sion follows a consonant other than r, it sounds exactly like -tion: /ʃən/.

• tension → TEN-shun
• mansion → MAN-shun
• pension → PEN-shun
• extension → ik-STEN-shun

This is why tension and intention end in the same sound, even though one is spelled -sion and the other -tion.

A Quick Decision Rule#

Look at the letter immediately before the -sion:

• Vowel before -sion → /ʒən/ (vision, occasion)
• r before -sion → /ʒən/ (version, excursion)
• Other consonant before -sion → /ʃən/ (tension, pension)

Stress Placement#

Getting the right sound is only half the work. You also need to stress the correct syllable, and these endings have a fixed rule: the stress falls on the syllable immediately before the -tion or -sion ending.

The ending itself is never stressed.

When learners stress the ending itself — "na-SHUN", "dih-sih-ZHUN" — the word sounds effortful and slightly foreign to a native ear, even if the consonant sounds are perfect. Stress placement, in other words, matters as much as the sounds themselves. You can read more about how stress and rhythm shape the way listeners perceive your English on the ummute benefits page.

A Worked Example#

Take the sentence:

"The final decision on production will be a question of communication."

Here is how each -tion and -sion ending should sound:

• decision → dih-SI-zhun (vowel before -sion → /ʒən/)
• production → pruh-DUK-shun (-tion → /ʃən/)
• question → KWES-chun (-stion → /tʃən/)
• communication → kuh-myoo-nih-KAY-shun (-tion → /ʃən/)

Say the sentence slowly first, placing each stressed syllable a little heavier than the rest. Then bring it up to a natural pace. You will notice that the rhythm of the sentence falls into place quite naturally once the stress is correct — the unstressed -shun and -zhun endings become light and quick, exactly as they should be.

A Short Drill#

Read this list aloud three times. On the first pass, exaggerate the stressed syllable before each ending. On the second, speak at a normal pace. On the third, try to say the whole list in one breath.

1. action — AK-shun
2. vision — VIZH-un
3. tension — TEN-shun
4. suggestion — suh-JES-chun
5. occasion — uh-KAY-zhun
6. extension — ik-STEN-shun
7. explosion — ik-SPLOH-zhun
8. question — KWES-chun

If you stumble on vision or occasion, spend a moment just practising the /ʒ/ sound on its own: zh... zh... vision. That sound rarely appears at the start of an English word, so it can feel awkward to produce until your mouth learns where to place it.

Recording Yourself#

One of the most useful things you can do is record yourself saying the worked example sentence above, then listen back. Most people are surprised to find they are stressing the ending ("na-SHUN") rather than the syllable before it. Your ear will catch what your tongue misses. If you want structured feedback on exactly this kind of pattern — not just these endings, but the full texture of how you sound — take a look at how ummute works.

The endings -tion and -sion appear in well over ten thousand common English words. Mastering three sounds — /ʃən/, /ʒən/, and /tʃən/ — and one stress rule will make every one of them easier to say, and easier for your listeners to understand.