PCAOB inspections repeatedly indicate deficiencies in audits of fair-value (FV) estimates, prompting regulators to improve the related auditing standards. We predict that auditor task-specific FV expertise, gained from work experience during the audit of FV measurements, can contribute to higher audit quality. Utilizing FV-related restatements and comment letters, we find that expertise in auditing Level 3 FV estimates at the office level is associated with greater FV audit quality. Level 2 FV expertise or national level FV expertise is not associated with higher FV audit quality. Following the receipt of a comment letter, we further find that auditor FV expertise is associated with lower comment letter remediation costs and higher FV disclosure quality. Finally, we find that the value relevance of Level 3 FV disclosures increases with the extent of auditor FV expertise. Collectively, our results highlight that auditor fair value expertise contributes to the credibility and usefulness of FV disclosures.