Surcharge is the primary monetary remedy for a proven breach of fiduciary duty by a trustee, executor, personal representative, guardian, or conservator, and it is measured by the loss the breach actually caused — commonly the difference between what the trust or estate would have been worth absent the breach and its actual value, though where the breach involves an improper gain to the fiduciary, disgorgement of that gain can be assessed instead or in addition. Surcharge is a personal liability of the fiduciary, not merely a reduction of what they would otherwise be paid in compensation.

Courts calculating surcharge often rely on expert testimony to establish what a prudent fiduciary would have done and what result that alternative course would have produced, since simply showing a loss occurred is not enough — the loss must be causally connected to the breach itself rather than to market conditions or other independent factors a prudent fiduciary could not have avoided. Fiduciaries can reduce or defeat surcharge exposure by showing they acted reasonably and in good faith, that beneficiaries consented to or ratified the challenged conduct, or that a valid exculpatory clause limits liability for the conduct at issue.

Juricratic models surcharge exposure using the same damages-modeling framework as other litigation loss calculations, treating the causal link between the breach and the claimed loss as its own dial separate from whether a breach occurred at all, since a breach without a provable causal loss typically produces little or no surcharge.

Fiduciary litigators build surcharge claims around a clear counterfactual — what a prudent fiduciary would have done differently and what result that would have produced — usually supported by a financial or investment expert, because courts require the loss to be causally tied to the breach rather than simply pointing to a decline in account value.