All Euro banknotes have a one-letter, eleven-digit serial number located on the back at the top right and bottom left corners of every denomination. The letter indicates which NCB has issued the banknote. Serial numbers of the Euro banknotes are not sequential. Rather, they contain both a check digit and a checksum. No serial number is ever repeated twice within one denomination; though two serial numbers may exhibit matching digits, the letter will differ.

Check Digit

A check digit can be used to verify authenticity of the actual serial number. The universal check digit is 8 for Euro banknote serial numbers. It is obtained by replacing the initial letter in the serial number with its corresponding position in the Latin alphabet (A=1, B=2...Z=26), then adding each subsequent digit to this. The subsequent digits of this result are then added to equal 8.

Check Digit Examples
Serial Number Initial Letter Letter/Digit
Conversion
Digits Equation Result Second
Equation
Check
Digit
L00105481787 L 12 00105481787 12+0+0+1+0+5+4+8+1+7+8+7 53 5+3 8
P00641307178 P 16 00641307178 16+0+0+6+4+1+3+0+7+1+7+8 53 5+3 8
S00630387745 S 19 00630387745 19+0+0+6+3+0+3+8+7+7+4+5 62 6+2 8
Z10708476264 Z 26 10708476264 26+1+0+7+0+8+4+7+6+2+6+4 71 7+1 8
V02387040034 V 22 02387040034 22+0+2+3+8+7+0+4+0+0+3+4 53 5+3 8

Checksum

Like the check digit, the checksum is also used to verify the authenticity of the serial number. The checksum is predetermined based on the national identification letter ordered alphabetically by NCB name in its own language and then associated with a number ranging between 1 and 9, repetitively, in reverse alphabetical order. The checksum is obtained within the serial number by adding each subsequent digit. The result should match the predetermined checksum.

National identification codes for NCBs
and their associated checksum digit
Code Country Checksum
in English in official language
Z Belgium BelgiŽ/Belgique/Belgien 9
Y Greece Ελλάδα [Ellada] 1
X Germany Deutschland 2
(W) (Denmark) Danmark (3)
V Spain EspaŮa 4
U France France 5
T Ireland …ire/Ireland 6
S Italy Italia 7
(R) (Luxembourg) Luxembourg/Luxemburg/LŽtzebuerg (8)
(Q) Not Used
P Netherlands Nederland 1
(O) Not Used
N Austria ÷sterreich 3
M Portugal Portugal 4
L Finland Suomi/Finland 5
(K) (Sweden) Sverige (6)
(J) (United Kingdom) United Kingdom (7)
(I) Not Used
H Slovenia Slovenija 9
G Cyprus Κύπρος/Kıbrıs 1
F Malta Malta 2
E Slovakia Slovensko 3

For more detailed information regarding the National Identification codes used in Euro banknote serial numbers, see Which country are the Euro Banknotes from?

In cases where the checksum results in a double digit number, only the first digit is read as the checksum.

Checksum Examples
Serial Number National
Identification Code/
Checksum
Equation Result Second
Equation
Checksum
L00105481787 L/5 0+0+1+0+5+4+8+1+7+8+7 41 4+1 5
P00641307178 P/1 0+0+6+4+1+3+0+7+1+7+8 37 3+7 10 (1)
S00630387745 S/7 0+0+6+3+0+3+8+7+7+4+5 43 4+3 7
Z10708476264 Z/9 1+0+7+0+8+4+7+6+2+6+4 45 4+5 9
V02387040034 V/4 0+2+3+8+7+0+4+0+0+3+4 31 3+1 4