Common Polish Spelling Mistakes: ó or u, rz or ż, ch or h, and nie (Polish Spelling Checker Guide)

CorrectNow Editorial Team · 6 min read

Polish spelling is hard for one simple reason: several pairs of letters sound the same. Ó and u, rz and ż, ch and h are pronounced alike in standard Polish, so your ear cannot tell you which one to write.

The good news is that many words follow patterns. Related forms, typical endings and a few fixed rules settle most cases. This guide covers the four most common problem areas with examples a Polish teacher would use, plus the words you simply have to memorise.

ó or u: look for a related form with o

The most useful test for ó is alternation. If a related form of the word has o, write ó: stół and stoły, wóz and wozy, róg and rogi, mróz and mrozy. The ending -ów, used in place names and in the genitive plural, is also written with ó: Kraków, domów, kotów.

U is the usual choice in verb forms ending in -uje, such as maluje, pracuje and kupuje, and in nouns ending in -unek, such as rysunek. Words also normally start with u, as in ucho, ulica and uczeń. The exceptions include ósmy and ówczesny.

Some common words, like góra and który, have ó without a handy related form. These have to be learned.

Incorrect: stul – Correct: stół (Related form: stoły.)
Incorrect: pracóje – Correct: pracuje (Verb forms ending in -uje use u.)
Incorrect: Krakuw – Correct: Kraków (The ending -ów is written with ó.)

rz or ż: check for r, g or z in related words

Write rz when a related form has r: morze and morski, dobrze and dobry, góra and na górze. Rz is also written after the consonants b, p, d, t, g, k, ch, j and w, as in brzoza, przyjaciel, drzewo, trzeba, grzyb and krzesło. A few words break this pattern and use sz instead, such as pszczoła, pszenica and kształt.

Write ż when a related form has g, z or s: noga and nóżka, waga and ważyć, wozić and wożę.

One pair shows why this matters: morze means sea, while może means maybe or he can. Both are real words, so a basic spell checker that only checks whether a word exists will accept either one.

Incorrect: żeka – Correct: rzeka (Rz is the correct spelling of the word for river.)
Incorrect: pszyjaciel – Correct: przyjaciel (After p, write rz.)
Incorrect: To morze być prawda. – Correct: To może być prawda. (Może means maybe; morze means sea.)

ch or h: the h words are worth memorising

Ch is far more common than h, and it often alternates with sz: mucha and musze, ucho and uszy, cicho and ciszej. At the end of a word, ch is the usual spelling, as in dach, strach and orzech, and in the locative plural ending -ach, as in w domach.

H appears mainly in loanwords and in a limited set of native words. Common examples are herbata, hałas, historia and hotel. The practical approach is to learn the h words you use often and assume ch elsewhere, checking in a dictionary when unsure.

Incorrect: cherbata – Correct: herbata (Herbata is written with h.)
Incorrect: hmura – Correct: chmura (Chmura is written with ch.)
Incorrect: dah – Correct: dach (Ch is the usual spelling at the end of a word.)

nie with verbs: written separately

The particle nie is written separately from verbs: nie wiem, nie mam, nie lubię, nie idę. This is one of the most frequent mistakes in quick messages, where people join the two words.

The exceptions are verbs that do not exist without nie, such as nienawidzić and niepokoić. Since there is no verb nawidzić, nienawidzę is written as one word.

With adjectives and nouns the default is the opposite: nie is usually joined, as in niedobry, niemiły, nieprawda and nieporządek. Adjectives in the comparative are written separately, as in nie lepszy, and so are adjectives used in a direct contrast.

Incorrect: niewiem – Correct: nie wiem (nie with a verb is written separately.)
Incorrect: nielubię – Correct: nie lubię (Same rule.)
Incorrect: nie nawidzę – Correct: nienawidzę (This verb does not exist without nie.)
Incorrect: To nie prawda. – Correct: To nieprawda. (With a noun, nie is joined.)

A short routine for proofreading Polish

For longer texts, a Polish spelling checker that reads context is worth using alongside these habits. CorrectNow flags spelling and grammar issues in Polish, explains each change and keeps your sentence structure as you wrote it.

For every ó, rz, ż, ch or h you are unsure of, try another form of the word: plural, diminutive or a related adjective.
Check every nie: is the next word a verb? Then add a space.
Look twice at real-word pairs such as morze and może, where a spell checker that ignores context will not help.
Keep a personal list of the words you get wrong and review it.

Frequently asked questions

Is there a rule for every word with ó or rz?

No. Alternation and typical endings cover many words, but some, such as góra, który and rzeka, have to be memorised.

Is nie always separate from verbs?

Almost always. The exceptions are verbs that only exist with nie, such as nienawidzić and niepokoić.

Why did my spell checker accept morze where I meant może?

Both are real Polish words, so a spell checker that only checks whether a word exists will accept either. Only the context shows the error, which is why a context-aware check and a careful reread both help.

Can I rely on a checker for official Polish documents?

Use it to catch most mistakes, but have an official or legal document read by a fluent Polish speaker before you send it.

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