NOXFORD ID is a seven-layer privacy-preserving identity verification architecture designed to address a specific fraud vulnerability in cross-institutional identity validation: the brittleness of exact-match verification against ordinary, legitimate variation in how names and dates are recorded across institutions. The architecture combines hardened Bloom-filter cryptographic linkage (privacy-preserving record linkage), field-separated fuzzy matching, a probabilistic decision engine with an explicit human-review tier, a tamper-evident cross-institutional integrity ledger, a genuine Schnorr zero-knowledge proof of identity knowledge, replay-resistant institution-specific key derivation, and a Root Certificate Authority layer aligned with Nigeria's NIMC Act 2026, which designates the National Identity Management Commission as Root Certification Authority for the country's National Public Key Infrastructure. Each layer is independently implemented and empirically tested against a labeled test corpus, with results reported transparently, including design flaws discovered and corrected during development. The paper documents a measured reduction in false rejection of legitimate citizens from 57% to 14% relative to a representative exact-match baseline, while maintaining zero fraud slip-through in testing, and explicitly states the system's current limitations, including evaluation corpus scale, dependence on enrollment-data integrity, and pending network-level threat-detection integration.