Answer
Both are crimes against property, but they differ in how the property is taken. Theft under Article 308 of the Revised Penal Code is committed by taking another's personal property without the owner's consent, with intent to gain, and without violence, intimidation, or force.
Estafa under Article 315 involves no such taking; instead the offended party parts with the property because of the offender's deceit or abuse of confidence. In short, theft is taking without consent, while estafa is obtaining through fraud — a distinction that often decides which crime is properly charged.
Sources & further reading
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