Landed cost: the only price worth comparing

The formula

Landed cost = item price + shipping + tax. Each term is sourced independently and each carries its own availability flag. When a term is unavailable, MarginMap shows the partial total and marks it partial — it does not silently substitute an average.

Item price

The seller's current asking price in the offer currency, excluding promotional strikethroughs that are not actually applied at checkout.

Shipping

Destination-aware. Free-shipping thresholds are evaluated against the item price rather than assumed.

Tax

Applied where the source publishes a rate or the destination rule is unambiguous. Otherwise flagged as unknown.

Why the cheapest sticker is often not the cheapest purchase

Ordering by item price reorders once shipping is added and reorders again once tax is applied. On mid-priced electronics the gap between the cheapest sticker and the cheapest landed cost routinely runs 8 to 22 percent, and the winner changes in roughly a third of comparisons.

MarginMap sorts and scores exclusively on landed cost, so the ranking you see is the ranking you would experience at checkout.

Missing data is labelled, never imputed

Imputed tax is the single easiest way to make a tool feel authoritative and be wrong. A guessed rate that is two points off turns a thin margin into a loss and the user never sees the assumption that caused it.

When a tax rate is unavailable, the offer carries a visible unknown-tax flag, the comparison notes that totals are not strictly comparable, and data confidence drops. The decision stays with you, informed.

Cross-border and returns

Import duty, customs handling and currency conversion are treated as first-class cost lines when the corridor is known. Return shipping is not folded into landed cost, because it is conditional — it appears instead as a risk note on the offer, alongside the seller's stated return window.