Two verbs, two intensities
Spanish has two common verbs that can both be translated "to love": querer (whose core meaning is closer to "to want" or "to care for") and amar (a more elevated, specifically love-focused verb). Te quiero and te amo — "I love/want you" and "I love you," respectively — pull from those two verbs, and native speakers treat them as genuinely different statements, not stylistic variants of the same one.
Te quiero: the everyday version
Te quiero is the more common of the two by a wide margin, and it's used across a much wider range of relationships: friends tell each other te quiero, family members say it routinely, and romantic partners use it too, especially outside of the most serious or formal declarations. Because querer also means "to want," the phrase carries a lighter, warmer connotation of care and affection rather than an all-consuming romantic claim — closer to "I care about you deeply" than to a wedding-vow-level statement.
If you're unsure which to use with a new romantic partner, te quiero is the safer default precisely because it doesn't overcommit.
Te amo: saved for something bigger
Te amo is reserved, by convention, for deeper, more serious romantic love — the kind of statement that typically comes after a relationship has had real time to develop, not something said casually or early on. Using it too soon in a new romance can read as unexpectedly intense or even a little theatrical to a native speaker, roughly the way declaring "I am deeply, permanently in love with you" would land oddly if said to someone you'd been dating for two weeks.
Romantic intensity isn't the only place te amo shows up, though: in Mexico and especially in Argentina, it's also commonly used between parents and children, as a sign of serious, weighty affection rather than romance. So "almost always romantic" is the right instinct for a new acquaintance, but not an absolute rule — the common thread across every use of te amo is depth of feeling, not necessarily romance specifically.
A regional wrinkle worth knowing
The intensity gap between the two phrases holds everywhere Spanish is spoken, but which one gets used day-to-day varies by region. In Spain, te quiero is the phrase couples typically use even in long-term, committed relationships — te amo can sound almost too formal or literary for everyday use. In much of Latin America, both phrases are in active use, with te amo more reliably reserved for genuinely serious romantic love and te quiero covering everything from friendship to an early relationship.
For a warm, clearly non-romantic alternative — telling a friend you value them without touching either "love" verb — Spanish speakers often reach for me caes muy bien ("I like you a lot," literally closer to "you strike me very well") instead.
A third rung below both: "me gustas"
There's a lighter step below even te quiero for early romantic interest: me gustas ("I like you," in the sense of "I'm into you," not the plain-liking sense of me gusta for a food or a movie). It signals attraction without committing to anything like love — closer to a crush confession than a relationship milestone, and often what gets said before either te quiero or te amo is on the table at all.
Put in order of escalating commitment, the three sit roughly as me gustas (attraction, no commitment implied) → te quiero (affection, appropriate for friends, family, and established but not necessarily deeply serious romance) → te amo (deep, committed romantic love). None of the three is interchangeable with either of the others.