Rule 424 (b) (3)  
     Registration No. 333-210526  
       
     U.S. $20,000,000,000.00  
     National Rural Utilities CFC  
     VARIABLE DENOMINATION FLOATING  
     RATE DEMAND NOTES  
       
       
     Pricing Supplement No.31 March 17, 2017  
     TO PROSPECTUS Dated March 31, 2016  
       
 Interest Rate:      0.750%    per annum  
     Rates will be set daily. Eligible Investor [1] will purchase a Variable Rate Note, containing a promise  
     from CFC to repay the note plus interest upon the receipt of a Redemption Notice from the Eligible  
     Investor.  
       
 Period   Beginning:      March 17, 2017  
       
       
       
       
     [1] Generally CFC members and other rural utilities which have been determined to satisfy federal and       
     state eligibility criteria.