The Internal Revenue Service (IRS) and the Internal Revenue Code (IRC) require Northwestern Mutual mail Form 1099–R and 1099–INT to the taxpayer by January 31st (or the next business day if January 31st falls on a weekend or legal holiday) of the year following the year in which the distribution took place or the interest was earned. Example: A reportable transaction occurs by December 31st then a tax form 1099 needs to be sent by January 31st of the following year. Given the large volume of tax forms mailed during January, it may take several days for the form to reach the taxpayer.Form 1099s are also available through the Northwestern Mutual website as early as February 1st