A recent US Tax Court case summarizes how a taxpayer who tried to save a few dollars on Federal Express shipping services most likely cost them thousand of dollars.
In the court case, the taxpayer had received a deficiency notice from the IRS on April 8, 2011. The taxpayer had until July 7, 2011 to mail the appeal to the tax court. The taxpayer mailed the appeal using Federal Express "Express Saver Third business day" option.
The IRS has a list of approved shipping services that qualify as valid shipping services to be used for timely filed petitions, etc.
Many of the Federal express products such as Priority Overnight, Standard Overnight, FedEx 2nd Day are listed as approved, however, the 3rd day option is not listed.
Therefore, the taxpayer by trying to perhaps save $5 on shipping costs had their whole Tax Court appeal denied and I am not sure how much was involved, but it does not pay to overlook the fine print on IRS and Tax Court appeals.