The Act empowered the Postmaster-General to require the railway companies to "convey the mails", either by special trains or scheduled ones, at such times of the day and night as he would direct; he also had power to specify the guards or postal officials to be carried.

However, he could not require they be conveyed any faster than the maximum rate prescribed by that railway's directors for first-class trains.

The Act did not specify a rate of payment, but rather left the remuneration to be agreed between the railways and the Postmaster-General, or if necessary settled by arbitration.

Individual lessees of a railway, those not a body corporate or company, were not to be required to give security above £1,000.

Finally, two arbitrators were to be appointed to mediate disputes between the Postmaster-General and the railway companies.