Bundle pricing combines several products or services behind one blended price. In its honest form it is a genuine convenience and often a real saving — a software suite or a family data plan can legitimately cost less together than assembled piece by piece. The tactic turns manipulative when the single price is engineered to obscure per-item value: bundling a product you want with one that is overpriced or unwanted, so the weak component rides along invisibly and the total spend rises.
The mechanism is framing plus deliberate complexity. When items carry no visible individual price, you cannot easily compare each against alternatives, so you evaluate the package as a whole against an inflated “total value” anchor (→ Price Anchoring, T8.2). Behavioral pricing research shows people struggle to disaggregate blended prices and tend to accept the bundle if the headline discount looks large — even when they’d reject the padding item on its own. The larger and more mixed the bundle, the harder this arithmetic becomes, which is precisely the point.
Defense is straightforward once you slow the transaction down: price each component separately, add up only the pieces you would have bought anyway, and disregard the “total value” sum entirely. If a seller won’t provide à la carte pricing, treat that opacity as the tell. A bundle that gets more attractive the more closely you itemize it is honest; one that only looks good as an undifferentiated lump is hiding something.