| 1718 | 1719 | |
| Gross Produce from Letters | £14,592 | £19,522 |
| Charge of Management and Members' Letters | 11,526 | 18,768 |
| Net Produce from Letters[636] | 3,066 | 754 |
Under the charges of management is included the charge for carrying members' letters as reckoned proportionately to the charge for the letters which paid, together with the actual charge for the pay letters. The net produce during the three months' session was £3006, during the nine months' session only £753. In 1734 the old orders about the maximum weight of two ounces and the requirement for the whole superscription to be in the member's own writing were repeated in a royal proclamation. In addition it was ordered that any letters sent under cover to any member of Parliament or high official of state, to be forwarded by him, should be sent to the General Post Office to be taxed.[637] It could hardly be expected that this order would be obeyed, for there was no method of enforcing it.
In 1735, the House of Commons instituted an enquiry into the whole question of franking and summoned various Post Office officials before them to give evidence. An estimate was laid before them of the amount lost each year by carrying franked letters. This estimate was obtained by weighing the franked letters at intervals during the session of Parliament, and comparing their weight with the weight of the letters which paid postage. As the total revenue from the latter was known, the amount which was lost on the former was guessed. The House expressed very little confidence in the estimated amounts, and certainly it was a rough way of attaining the object aimed at, but perhaps they were prejudiced from the strength of the case against them.[638] Expressed in yearly averages, the amounts by which the revenue was reduced by franking were:—
| 1716-19 | £17,460 | 1725-29 | 32,364 | |
| 1720-24 | £23,726 | 1730-33 | 36,864 |
The system of ascertaining forged franks and of discovering enclosures was as follows: a Supervisor of the Franks charged all letters, franked by a member's name, coming from any place, when he knew that the member was not there. Very often by holding them in front of a candle, he could see enclosures inside directed to other people. If he was in doubt he generally charged the letter, for if it should pay, all well and good, and if he had made a mistake, the amount was refunded to the member. The Supervisor had noticed that the number of franked letters had increased with every session of Parliament, and some of the ex-members also attempted to frank letters. The evidence of the Supervisor, especially his description of the manner in which he attempted to discover enclosures, was exceedingly distasteful to the House. The members themselves were to blame for many of the abuses attendant upon the system, and yet they contended that they were the unwilling victims of others. A resolution was adopted that it was an infringement upon the privileges of the knights, citizens, and burgesses chosen to represent the people of Great Britain in Parliament, for any postmaster, his deputies or agents to open or look into any letter addressed to or signed by a member of Parliament, unless empowered so to do by a warrant issued by one of the Secretaries of State. In addition no postmaster or his deputies should delay or detain any letter directed to or by any member unless there should be good reason to suppose that the frank was a counterfeit.[639]
The restrictions adopted to curtail the abuse of the franking privilege had but little effect. A regular business sprang up for selling counterfeit franks. The House of Lords ordered one person accused of selling them to come before the bar of the House for examination, but he failed to present himself.[640] Another confessed before the Upper House that he had counterfeited one of the Lords' names on certain covers of letters showed to him and had then sold them. He expressed sorrow for the offence, which necessity had driven him to commit. He was sent to Newgate.[641] The abuses of the franking system were so patent[642] that Allen was told that he might withdraw from his contract to farm the bye and cross post letters on three months' notice being given.[643]
The revenue from the Post Office was surrendered by the Crown at the beginning of George the Third's reign in exchange for a Civil List from the Aggregate Fund as it was then called.[644] While the Post Office remained in the hands of the King, it was only by special grant on his part that the members of Parliament had been allowed to send and receive letters free. Accordingly in 1763, an act was passed for the purpose of giving parliamentary sanction to the privilege. This act repeated the principal points in the King's proclamation and in the Parliament's previous resolutions on the subject. All letters or packets sent to or by the King, the ministers and the higher Post Office officials were to go free. The ministers might appoint others to frank their letters, whose names must be forwarded to the Postmaster-General. Those sending letters free must sign their names on the outside and themselves write the address. No letters to or from any member of Parliament should go free unless they were sent during the session or within forty days before or after, and the whole superscription must be in the member's own hand or directed to him at his usual place of residence or at the House. All letters in excess of two ounces in weight must pay postage. Printed votes, proceedings in Parliament, and newspapers should go free when sent to a member or signed on the outside by him, provided they were sent without covers or with covers open at the ends. The privileges of franking votes, proceedings in Parliament, and newspapers, were continued to the clerks in the Post Office and in the Secretaries of State's offices. The Postmasters-General and their deputies were given authority to search newspapers which had no covers or covers open at the ends and to charge them if there were writing or enclosures in them. Finally, any person who counterfeited a member's name on any letter or package for the purpose of avoiding the payment of postage, was guilty of felony and liable to transportation for seven years.[645]
The year following the passing of this act, the House of Commons called for returns relating to the franking system. Besides the members of Parliament, the ministers, and the Post Office officials, to whom the franking privilege had been granted by the King's warrant and by the late act, almost all who were in any way connected with the Government claimed the right to send or receive letters free, even to the Deputy Serjeant-at-Arms. The amount which newspapers would have paid if there had been no franking privilege was first given for the week ending March 13, 1764.
| Members' | States' | Post Office Clerks' |
| £465 | £310 | £1055 |
These amounts were obtained by weighing the newspapers and, as this was the manner in which they would have been rated, the results may be considered as fairly correct. The idea being to estimate the loss from members' and states' franks only, the franking by Post Office clerks does not enter into the following calculation. It was judged from the figures given above that the Post Office carried free every year enough newspapers franked by members and state officials to produce £40,000 if they had been taxed at the ordinary rates.[646] An attempt to arrive at the same result in another way was also made. The sum total which would have been paid on all members' and ministers' letters, newspapers, and parcels arriving at or departing from London in 1763 was £140,000. Of this amount £85,000 would have been paid on all mail leaving London, and £55,000 on all mail arriving in London. The difference in favour of the outgoing mail was judged to be due to the newspapers, all of which were printed in London and sent to the country. This would give a loss of £30,000 on newspapers, and £110,000 on letters.[647]