Spanish Accent Marks: 3 Rules for Every Word

Most accent guides hit you with four Greek-sounding category names on the first screen — aguda, llana, esdrújula, sobresdrújula — and three sub-rules under each. Twelve cases to juggle, and you still can’t say whether examen needs a tilde (it doesn’t) while exámenes does. That’s backwards. The tilde isn’t decorative and it isn’t random: it’s a repair mark. Spanish has exactly one default stress pattern, and an accent shows up only when something overrides it. Learn the default, learn the three overrides, and you’ve covered every word in the language.

One thing to clear up first: stress and the accent mark are not the same. Every Spanish word has one loud syllable. Only a minority wear a written tilde. The mark just tells you the loud syllable isn’t where you’d guess — so it’s really a pronunciation cue, not a spelling quirk. If you can hear the stress, you can place the mark.

First, the default every word already follows

Before any tilde exists, Spanish tells you where the stress falls from a single clue: the last letter of the word.

Spanish	English	Stress
casa	house	CA-sa
joven	young	JO-ven
lunes	Monday	LU-nes
hablar	to speak	ha-BLAR
ciudad	city	ciu-DAD
feliz	happy	fe-LIZ

The rule has two halves. If the word ends in a vowel, -n, or -s, stress the second-to-last syllable (casa, joven, lunes). If it ends in any other consonant (-r, -l, -d, -z…), stress the last syllable (hablar, ciudad, feliz). That’s it. A word that obeys this carries no accent, because it’s already pronounced exactly where the rule predicts. Notice how common the “soft” endings are — plural -s, verb endings -n and -o — so most everyday words sit on the second-to-last syllable by default.

Rule 1: mark the word when it breaks the default

This single rule covers the large majority of accented words. Say the word aloud, find the loud syllable, and ask: does the default already put stress there? If yes, no mark. If no, write a tilde over the stressed vowel. The category names are just labels for where it broke.

When stress lands on the last syllable but the word ends in a vowel, -n, or -s, the default guessed wrong — so it gets a tilde:

Spanish	English
canción	song
también	also, too
café	coffee
país	country

Compare canción, también, and café to casa: all end in a soft letter, but the stress jumped to the end, so each needs the mark.

The mirror case: stress on the second-to-last syllable when the word ends in a consonant other than -n/-s. The default expected last-syllable stress, so again you repair it — árbol (tree), fácil (easy), lápiz (pencil).

And when the loud syllable is the third from the end or earlier, the word always takes a tilde — no default ever reaches that far back. Think música, teléfono, sábado, rápido. These are the words English speakers mangle most, drifting into TEL-e-phone instead of te-LÉ-fo-no. Tap any of them above to hear where the stress really lands.

Rule 2: mark the word to tell look-alikes apart

Some pairs are spelled identically and sound identical — the tilde carries no sound difference at all. It’s a purely visual tag so the reader knows which word you mean. The accented member is usually the “content” word (a pronoun, adverb, or verb); the bare one is grammatical glue. The list is short and fixed, so memorize it once.

With tilde	Without tilde
tú	tu — you (subject) vs your
él	el — he/him vs the
sí	si — yes vs if
más	mas — more vs but (literary)
té	te — tea vs you (object)

In context the pairs are obvious: Tú tienes que traer tu camiseta (“You have to bring your shirt”), or A mí me gusta mi casa (“I like my house”). Want a drink? ¿Quieres un té? Te lo preparo. Get más and mas mixed up and a native reader still understands you — but the homophone tilde is exactly the kind of small slip that marks a sentence as non-native, so it’s worth the five minutes to lock in.

Rule 3: mark a weak vowel that splits off (hiatus)

This is the rule learners miss most, because it looks like Rules 1 and 2 are being broken. Spanish vowels come in two strengths: strong (a, e, o) and weak (i, u). When a weak vowel sits next to a strong one, the default is a diphthong — both vowels share one syllable (bai-le, cua-tro). But when the weak vowel is the one carrying the stress, the pair splits into two syllables, and you must write a tilde on that weak vowel to make it stand alone.

Spanish	English	Syllables
día	day	dí-a
río	river	rí-o
país	country	pa-ís

Without its tilde, día would collapse into dia — one syllable, the wrong word. Same logic gives you río, baúl, tía, and the whole -ía/-ío family (comía, energía). The diagnostic is simple: a stressed í or ú next to another vowel is almost always a hiatus marker — its own syllable, standing on its own feet.

Two marks that aren’t accents

Don’t let these make you think the three rules failed. The squiggle over ñ (as in año, year) doesn’t mark stress — it makes a whole separate letter. Drop it and año becomes ano, a very different word. And the two dots in ü (pingüino, vergüenza) just mean “actually pronounce the u.” Both are pronunciation flags, never stress marks, and never optional.

You already know more than you think

Here’s the payoff: you don’t memorize twelve cases, you ask three questions. Does the stress break the default? Is it a homophone from the short list? Is a weak vowel splitting off? Run any Spanish word through that and you’ll know whether it wears a tilde. Since this is really a pronunciation skill, train your ear next — the same instinct that nails the stress in rápido powers the trilled sound in our guide to rolling your Spanish R. And once you trust your accents, you’ll spot the traps in our roundup of Spanish false friends. Read the next Spanish word you meet out loud, find the loud syllable, and check — you’ll be right far more often than you expect.