Previous work on Quality of Service in Cut-through networks shows that resource reservation mechanisms are only effective below the saturation point. Admission control in these networks will therefore need to keep network utilization below the saturation point, while still utilising the network resources to the maximum extent possible. In this paper we propose and evaluate three admission control schemes. Two of these use a centralised bandwidth broker, while the third is a distributed measurement based approach. We combine these admission control schemes with a DiffServ based QoS scheme for virtual cut-through networks to achieve class based bandwidth and latency guarantees. Our simulations show that the measurement based approach favoured in the Internet communities performs poorly in cut-through networks. Furthermore it demonstrates that detailed knowledge on link utilization improves performance significantly.