With advancements in quantum computing, existing public-key cryptographic standards such as RSA and
Elliptic Curve Cryptography (ECC) face an impending risk of obsolescence. These foundational systems underpin critical
components of secure communications, from VPNs to TLS-protected web traffic. This paper evaluates the current state
of enterprise preparedness for post-quantum cryptography (PQC) and proposes a structured transition roadmap. We
analyse leading post-quantum algorithms submitted to the NIST standardization process, particularly focusing on latticebased (Kyber, NTRU) and code-based (Classic McEliece) cryptosystems. Each is compared in terms of key size,
computational overhead, and deployment complexity. A cross-industry survey of 27 enterprise IT departments reveals a
significant preparedness gap: nearly half of respondents were unaware of quantum threats, and none reported a concrete
migration plan. Using simulation environments integrating OpenSSL and WireGuard, we assess performance impacts of
various PQC algorithms under realistic conditions. While post-quantum solutions do introduce increased computational
costs, our findings suggest they are viable for implementation in high-value and internal systems. The study concludes
by presenting a Quantum-Safe Readiness Model (QSRM), identifying phases of enterprise transition, and advocating for
immediate pilot testing and policy-level engagement. This research underscores the urgency of beginning the migration
process now to defend against potential “harvest now, decrypt later” scenarios exploited by advanced adversarie
