Apparatus and method for monitoring flow meter operation. In one embodiment, a flow metering system includes a flow meter and a condition monitor. The flow meter is configured to measure volume of fluid flowing through the flow meter. The condition monitor is coupled to the flow meter and is configured to monitor a parameter of operation of the flow meter, and to compare a value of the parameter to a threshold. The condition monitor is also configured to generate an alarm based on the value exceeding the threshold, and to compute, based on the alarm, a confidence level indicating a degree of certainty that the system is operating in accordance with predetermined criteria.