Every Esperanto letter has uppercase and lowercase forms, including Ĉ/ĉ, Ĝ/ĝ, Ĥ/ĥ, Ĵ/ĵ, Ŝ/ŝ, and Ŭ/ŭ. In ordinary prose, capitals mark the beginning of a sentence and the beginning of a proper name. Beyond that core, Esperanto has real editorial variation, so English capitalization cannot simply be copied word for word.
PMEG is explicit that Esperanto has no exhaustive binding rules for case. It describes widespread conventions and two broad tendencies: a common lowercase-leaning style and a rarer uppercase-leaning style. Good writing follows a coherent convention and uses capitals when they make structure or identity clearer.
The stable core
Use an initial capital at the start of a main sentence and for a proper name. Use lowercase for ordinary common nouns, adjectives, verbs, adverbs, pronouns, and grammatical words unless another convention applies.
Marta loĝas en Bruselo kun sia frato.
Marta lives in Brussels with her brother.
Marta and Bruselo are proper names; frato is a common noun. Esperanto does not capitalize an ordinary noun merely because it is important.
Ĉu Ĝoja jam revenis el Eŭropo?
Has Ĝoja already returned from Europe?
This sentence shows three uppercase diacritic letters. The diacritics remain in uppercase: Ĉ, Ĝ, and Ŭ are the case partners of ĉ, ĝ, and ŭ. Removing the marks creates different letters.
ŜI VENOS BALDAŬ.
SHE WILL COME SOON.
All-caps writing is possible (display/emphatic), and Ŭ has an uppercase form even though ordinary Esperanto words do not begin with ŭ. In normal prose, sustained capitals can feel like shouting, just as in English.
Unicode provides both cases directly, and those are the normal forms for finished text. The h-system (Fundamental fallback) and x-system (technical input convention) can also carry case information—an input tool may convert forms such as Cx or CX to Ĉ—but converter conventions differ. They are input encodings, not extra lowercase or uppercase letters, so check the converted Unicode result instead of publishing the raw code.
La programo konvertis la provizoran formon ‘CXU’ al ‘ĈU’.
The program converted the temporary form CXU to ĈU.
Countries, peoples, and languages
Country names are proper names and begin with capitals: Kanado, Japanio, Brazilo. Names for people and adjectives derived from place names are commonly lowercase in the now-dominant lowercase-leaning style: kanadano, japana, brazila. Some writers capitalize people names or derived adjectives, especially in an uppercase-leaning editorial tradition; that is accepted variation, not a different grammar.
Aiko estas japanino, sed ŝi nun loĝas en Kanado.
Aiko is Japanese, but she now lives in Canada.
Ni manĝis brazilan pladon en restoracio apud la hotelo.
We ate a Brazilian dish in a restaurant near the hotel.
Language names expressed as adjectives are usually lowercase: la angla, la japana, paroli france. True noun names of languages, especially planned or classical languages in -o, behave as proper names: Esperanto, Ido, Latino, Sanskrito.
Ni parolis angle pri Esperanto kaj poste legis tekston en Latino.
We spoke in English about Esperanto and then read a text in Latin.
Esperanto, esperanta, and Esperanta
The language name Esperanto is capitalized (neutral) because it is a proper name. A derived adjective or adverb is often lowercase: esperanta libro, paroli esperante. Capitalized Esperanta/Esperante also occurs and can clarify that the word concerns the language rather than the verb esperi, “to hope.”
Ŝi legis esperantan romanon dum la vojaĝo.
She read an Esperanto novel during the journey.
La esperanta studento atendis bonan rezulton.
The hopeful student was expecting a good result.
La Esperanta studento partoprenis lingvan kongreson.
The Esperanto-speaking student took part in a language congress.
This is a meaningful written contrast: esperanta can be the active participle “hoping,” while Esperanta can explicitly signal “related to Esperanto.” Context often removes the ambiguity, and lowercase esperanta meaning “Esperanto-related” is widespread. Capitalization here is a tool for clarity and tradition, not a spoken grammatical contrast.
Days, months, and holidays
Weekday names are ordinary common nouns and normally lowercase: lundo, mardo, merkredo. Month names have traditionally been treated as proper names and capitalized: Januaro, Februaro, Marto. Lowercase month names are now common in actual usage, although PMEG recommends the traditional capitalized forms. Holidays are normally proper names: Kristnasko, Pasko.
La kunveno okazos lunde, la dek-duan de Januaro.
The meeting will take place on Monday, the twelfth of January.
Ni restos hejme dum Kristnasko kaj vizitos ilin post la festo.
We will stay home during Christmas and visit them after the holiday.
Be honest about the variation: a lowercase januaro is well attested and immediately understandable, but a guide following PMEG’s recommendation will write Januaro. Within one publication, consistency matters more than switching styles unpredictably.
Respectful capitals and pronouns
The ordinary second-person pronoun is lowercase vi. Zamenhof often wrote Vi in letters to show special respect, but this use is now (formal, uncommon). It is not the Esperanto equivalent of mandatory German polite-pronoun capitalization. Dio is also sometimes capitalized as a mark of respect (religious/editorial).
Ĉu vi povus sendi la dokumenton hodiaŭ?
Could you send the document today?
Mi dankas Vin pro Via afabla respondo.
I thank you for your kind reply. (formal, uncommon respectful capitalization)
The second form is recognizable but marked. In an ordinary modern email, lowercase vi/via is neutral even when the message is polite.
Titles and word boundaries
Do not automatically import English headline capitalization, where Nearly Every Important Word May Receive a Capital. Esperanto titles frequently use sentence-style capitalization: capitalize the first word and genuine proper names. Publishers can adopt house styles, so this is a recommendation rather than a universal grammatical law.
Mi ĵus legis ‘Vojaĝo tra la norda Italio’.
I have just read ‘A Journey through Northern Italy.’
Case also interacts with word boundaries. If a compound visibly retains a capitalized name after a prefix, a hyphen often improves readability: ne-Esperanta, kontraŭ-Esperanta. A fully lowercase derivative may be written together: neesperanta. See word boundaries and hyphens.
La noto estas ne-Esperanta, sed la ekzemplo estas tute esperanta.
The note is not in Esperanto, but the example is completely Esperanto.
A short editorial exchange
— Ĉu mi skribu ‘angla’ per majusklo? — Ne necesas; en nia stilo ĝi estas minuskla.
— Should I capitalize angla? — No; in our style it is lowercase.
This answer states an editorial choice rather than falsely claiming that every other tradition is ungrammatical.
Common Mistakes
1. Copying English nationality capitalization. The common lowercase-leaning Esperanto style uses lowercase derivatives.
❌ Ŝi estas Kanada verkisto.
Nonstandard for this guide’s style — copying English capitalization into a derived adjective.
✅ Ŝi estas kanada verkisto.
She is a Canadian writer.
2. Removing a diacritic from a capital. Capital letters preserve their marks.
❌ Cu Simono venos Gis la oka?
Incorrect — uppercase C and G cannot replace Ĉ and Ĝ.
✅ Ĉu Simono venos ĝis la oka?
Will Simono come by eight?
3. Capitalizing every major word in a title by English habit. Use the publication’s Esperanto house style.
❌ Mia Vojaĝo Tra La Norda Italio
Poor Esperanto sentence-style title capitalization — copied mechanically from English.
✅ Mia vojaĝo tra la norda Italio
My journey through northern Italy.
4. Treating respectful Vi as mandatory. It is a marked, now uncommon option.
❌ Mi devas ĉiam skribi Vi al nekonato.
Incorrect — I must always capitalize vi when addressing a stranger.
✅ Mi povas ĝentile skribi vi per minusklo.
I can politely write vi in lowercase.
5. Mixing conventions inside one text. Accepted variation still calls for editorial consistency.
❌ En unu alineo mi skribas Januaro, januaro kaj JANUARO sen kialo.
Poor style — using three capitalization patterns in one paragraph without a reason.
✅ Mi elektas konsekvencan majuskladon por la tuta teksto.
I choose consistent capitalization for the whole text.
Key Takeaways
Capitalize sentence beginnings and proper names, preserve diacritics in capitals, and do not import English case patterns mechanically. Esperanto permits genuine editorial variation in derived proper-name words, months, titles, and respectful forms. Choose a recognized convention, label marked uses, and apply it consistently.
Related Topics
- The Esperanto AlphabetA1 — Learn Esperanto’s 28 letters, their names and order, and why the six diacritic letters count as letters in their own right.
- The Six Diacritic LettersA1 — Master ĉ, ĝ, ĥ, ĵ, ŝ, and ŭ as six independent Esperanto letters with distinct sounds and spelling roles.
- Capitalization in Titles and NamesA2 — Capitalize Esperanto titles and multiword names clearly without importing English title case or erasing accepted editorial variation.
- Foreign Names in EsperantoA2 — How to choose among full adaptation, partial adaptation, and original spelling while keeping names recognizable and usable.
- Accepted Variation and Personal StyleC2 — Distinguish stable grammar, accepted alternatives, register choices, individual style, and genuinely nonstandard forms in Esperanto.