There was one year several years back where Congress or the IRS allowed banks to get paperwork to people later. I forget what the reason was. But that year our 1099s only arrived around March 21st. And then after I filed my taxes around March 31 at least one bank hit me with an amended form right before the April 15 deadline. Thankfully it didn't make a difference in the tax I owed or critical numbers I had to report... though I had to go through the whole process of recalculation to determine that.