The newest $20 bill is the 2013 series (as of August 2014). They began printing them on October 2013 with the MA-A serial numbers.
Here's the stats for this bill...
Type/Federal Bank: $20 Star Note - D.C. / Philadelphia
Printed: December 2013
Run: Not known from MC32000001A - MC51200000A
Value: VF(very fine) $22.00
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