A lifetime income tax is an income tax that would tax a person based on their cumulative lifetime income, rather than their yearly income as is currently done throughout the world. A lifetime income tax is currently just a proposal that has been made by some economists and politicians.

The main advocate of the idea is Roger Martin, Dean of the University of Toronto's Rotman School of Management. Former Ontario health minister and Conservative Party of Canada leadership candidate Tony Clement has come out in favour of reforming Canada's tax code to embrace this notion.

Clement's plan makes a good example of such a system. Those who have earned less than $250,000 over their life time wouldn't have to pay taxes. Those who have made between $250,000 and $500,000 over their lifetime would be taxed at a 14% rate. Earners of a cumulative $501,000 to $750,000 would be taxed at a 24% rate, and those who had made $1 million over time would be taxed at 27%.

This system would have several advantages:

• It would help the young, the portion of the population most likely to make new purchases and those that are struggling with high interest rates, student loans, and young families
• It would put more of a tax burden on the middle aged and elderly who are more likely to save rather than spend and who have a generally higher standard of living.
• It could help cure Canada's "brain drain" of educated professionals emigrating to the United States.
• It would protect people against fluctuations from year to year.
• It would especially benefit those who have moved from a low income to a high income

The system would also have some disadvantages.

• It would tax seniors more heavily than any other group, and many seniors are not well off.
• It would reduce savings and thus decrease the amount of investment capital available in the society.
• It would make someone having a poor year even worse off as they would be paying taxes based on a number of earlier successful years
• It would hurt those who were once rich and are no longer wealthy

The system would maintain tax brackets that other alternative taxation schemes would do away with.

The implementation of the policy would also be difficult. Martin believes that before computers such a tax could not have been managed, but that it is today possible. The transition between systems would be difficult, taking many years. The politics of implementing such a system would also be difficult. Young people in much of the west are the least likely section of the population to vote, while seniors are the most likely, so that any system that transfers money from seniors to the young has a major hurdle to overcome.

Other proposed income tax systems

• flat tax
• negative income tax