The case for 'religion'
By any working definition, Buddhism qualifies: it has ordained clergy (the sangha, one of the oldest continuous institutions on Earth), temples and monasteries, scriptures (the Pali Canon and the Mahayana sutras), rituals, holidays, and roughly 500 million adherents practicing it as their tradition. Most Buddhists across Asia would find the question strange; it's their religion, with devotion, chanting, and merit-making as daily texture.
The case for 'philosophy'
Also real: Buddhism has no creator god, no required belief in one, and a founder who was explicitly a human being who figured something out. The Buddha's core teaching (the Four Noble Truths, the Eightfold Path) is a diagnosis of suffering and a practical method, closer in structure to a therapeutic program than a creed. The famous Kalama Sutta has him telling a village: don't accept teachings on authority, including mine; test them in experience. That's philosopher's talk, and it's why secular Westerners could extract meditation and ethics while leaving the cosmology at the door.
The honest resolution
The question assumes religion requires a god and philosophy excludes practice, and Buddhism politely breaks both assumptions. Scholars call it a non-theistic religion: a complete religious tradition organized around practice and insight rather than a creator. What you can say precisely: Buddhism functions as a religion for most of its adherents, works as a philosophy for readers who take the analysis without the cosmology, and was built as a practice either way. The parallel question, whether Buddhism is monotheistic or polytheistic, has an even cleaner answer.
Where to go deeper
The traditions differ on how religious the texture gets (Theravada austere, Tibetan devotional, Zen famously spare); our Buddhism for beginners guide maps the branches and the five books worth reading first, free. For the practice itself, the beginner's meditation method; for the daily-dose version of the tradition's actual voices, 365 Days of Zen carries the Zen lineage one page a day (★4.6 across 64 Amazon ratings).
Common questions
Is Buddhism a religion, yes or no?
Yes by function (clergy, scripture, ritual, 500 million adherents), with the caveat that it's non-theistic: no creator god and no required belief in one. Scholars class it as a religion; secular readers can and do engage it as philosophy and practice.
Do Buddhists believe in God?
Not in a creator God: the Buddha neither claimed divinity nor taught one. Buddhist cosmology includes deva realms (god-like beings), but they're mortal, unworshipped in the Western sense, and irrelevant to liberation, which comes from practice rather than grace.
Can you practice Buddhism without being religious?
Yes, and millions do: meditation, ethical precepts, and the analysis of suffering stand on their own, which is how secular mindfulness happened. Traditional Buddhists would note you're practicing a slice; the slice still nourishes.
What kind of religion is Buddhism classified as?
Non-theistic and universalizing: it centers practice and insight rather than a creator, and it accepts anyone rather than belonging to one ethnicity. It's counted among the world's major religions in every standard classification.