TCH and CH both spell the sound /tʃ/, like the start of chair. So why do we write catch with TCH but rich with just CH? A precise rule covers more than 95 percent of cases, and once you know it your spelling and your reading-aloud both improve.
The Rule in One Sentence
After a single short stressed vowel, write TCH. Everywhere else (long vowel, diphthong, after a consonant, or in an unstressed syllable), write CH.
Examples That Follow the Rule
- TCH after a short vowel: catch, match, fetch, ditch, dutch, scotch, hutch.
- CH after a long vowel/diphthong: teach, reach, couch, peach, vouch.
- CH after a consonant: march, lunch, bench, branch, punch.
Practice the Pattern
Why This Helps Pronunciation
TCH visually warns you: short, sharp vowel, then a quick crisp /tʃ/. CH alone usually signals a long vowel or diphthong. Recognising the pattern stops you from over-lengthening the vowel in catch or weakening the affricate in match into a soft /ʃ/.
Exceptions and Fine Print
The four classic exceptions are very common, very short words. Just memorize them:
- much, such, rich, which — short vowel but plain CH.
- attach, detach, sandwich, ostrich — plain CH because the final syllable is unstressed.
- bachelor, duchess — CH belongs to the next syllable.
Practical Tips
- When you read aloud, use TCH as a cue to keep the vowel short: catch, not "caaaatch".
- If a word came from Greek or French (e.g., chemistry, champagne), CH may stand for /k/ or /ʃ/, not /tʃ/. That is a different rule.
- When you write a new word from sound, ask: is the vowel short and stressed? Yes → TCH.
Related Lessons
Bottom Line: Short stressed vowel → TCH. Anything else → CH. Plus four classic exceptions: much, such, rich, which.