International Airlines' Western Air Express service operated during August and September 1933 between Croydon, Portsmouth, Southampton and Plymouth. The airline operated a short-lived airmail service for an additional fee of 3d, however, the service was unofficial and contravened the Post Office monopoly. Covers with a yellow label were carried on the first flight on 25th August, but due to bad weather at Plymouth the aircraft was unable to land and returned to Portsmouth, flying on to Plymouth the next day. A flight was also made from Plymouth to Croydon on the 24th August by some of the company's directors, who carried covers which were posted on arrival. Covers were also carried on 26th August and 1st September. The service was not widely advertised and did not last.

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