The search returned very few matches, most of which were not very helpful. However, we did find one web site that claimed the first income tax was paid only by the very wealthy, and they tended to spend their summers vacationing. Thus, the IRS Commissioner argued, "The collection of taxes would be much easier if an earlier assessment was made, before they leave town." And so it was. This information made sense and explained the general time frame for the deadline but didn't pinpoint why April 15 was chosen.

After several searches on variations of "tax day origin" proved unsuccessful, we changed tacks and tried "income tax history." We noticed that one of the results, Tax History Project, was a Yahoo! Pick, a definitive sign of a great site, so we headed on over.

Lo and behold, the very front page of the site offered us this tantalizing tax tidbit, "Until 1955, individual income tax returns were due on March 15, not April 15." We read on, confident that we were close to finding your answer. The history section of the site was very thorough and made for interesting reading but, unfortunately, did not elaborate on the origins of tax day. Looks like the front page fact was simply a teaser!

In a last-ditch effort to answer your question, we searched on the unwieldy "how did april 15 become tax day" and were promptly rewarded with a fortune -- a Fortune.com article that is.

The article explains that Congress passed the Sixteenth Amendment to the Consitution, which allows for the implementation of personal income tax, on February 3, 1913, and chose March 1 of the following year as the filing deadline. The deadline was changed to March 15 in 1918, and, as we learned at Tax History Project, to April 15 in 1955. Moving back the date from the end of the tax year served two purposes -- it gave the IRS more time to handle the work and, more importantly, more time to hang on to your money before issuing you a refund.