Bulk Limit

• You may send handwritten 1099s to the IRS provided that you are sending fewer than 250 of them. Anyone required to file more than 250 versions of a single form must file them electronically. The IRS publication 1220, updated yearly, explains the electronic filing process for form 1099 and forms like it.
  
  

Style

• Make sure that your handwriting is legible and unambiguous, and double-check every number you enter, especially ID numbers like your Social Security or Taxpayer Identification Numbers. Letters should be block-printed and clear, particularly on Copy A of the 1099, which will be read by machine.
  
  

Symbols

• Dollar signs are pre-preprinted on the form; do not add dollar signs of your own. Ampersands, asterisks, commas and apostrophes should all be eschewed as well, as should number signs -- "APT 4" rather than "APT #4." Do include the decimal points and cents of each value you write in a number box, and if a box requires no entry, leave it blank rather than entering zeroes.
  
  

Getting Help

• In the section of the 1099 rules allowing handwritten forms, the IRS recommends working with an IRS-partnered tax aid to ensure that everything on your form is accurate and doesn't conflict. You can find such IRS partners by going to IRS.gov and typing "e-file for business partners" into the Search box.