An MPAN (Meter Point Administration Number) is a unique number to the property. It is found on the electricity bill issued by your supplier. This is sometimes called a Supply Number but it should not be confused by your customer reference number
The full MPAN is 21 digits in length and should be printed in the format below on a recent electricity bill.
  
If you wish to find out your MPAN you can call your local electricity supplier - whose telephone number you will can see at MPAN Requests.
If you ask for their MPAS department they should be able to either tell you the full 21 digit MPAN or arrange to send it to you.
For a detailed explanation of your MPAN see the following:
Profile Class
Every property has a profile class.
Profile classes are used where half -hourly metering is not installed and provides the electricity supplier with an expectation as to how electricity will be consumed throughout the day.
From a domestic customer viewpoint we are interested in two classes 01 and 02. Other classes that exist are 03, 04, 05, 06, 07, and 08. Where half-hourly metering is installed (large consumers) the profile class in 00.
Detailed below are the profile classes used as guidance to show your likely electricity consumption throughout the 24 hour period. You will notice that summer and winter figures are different:
01 Domestic Unrestricted

02 Domestic Economy 7

03 Non-Domestic Unrestricted

04 Non-Domestic Economy 7

05 Non-Domestic Maximum Demand 0-20% Load Factor

06 Non-Domestic Maximum Demand 20-30% Load Factor

07 Non-Domestic Maximum Demand 30-40% Load Factor

08 Non-Domestic Maximum Demand >40% Load Factor

Meter Time Switch Code (MTC)
The Meter Time Switch Code indicates how many registers (set of meter reads or dials) your electricity meter has and what times they will operate during the day. The Meter Time Switch Code will show if your meter has two registers, one which records day consumption, the other night.
Line Loss Factor (LLF)
The Line Loss Factor code stipulates the expected costs the distribution company will charge the supplier for using the cables and network in your region. This Line Loss Factor code will also indicate to the electricity supplier the potential charges incurred, due to loss of energy incurred whilst getting the electricity supplier to your meter.
Distributor ID
The Distributor ID will identify the local Distribution Company for your electricity supply. The Distribution company is responsible for management of the distribution system and electricity wires which transports the electricity to your meter.
                10 - Eastern Electricity 
                11 - East Midlands Electricity 
                12 - London Electricity 
                13 - MANWEB 
                14 - Midlands Electricity 
                15 - Northern Electricity 
                16 - NORWEB 
                17 - Scottish Hydro-Electric 
                18 - Scottish Power 
                19 - Seeboard 
                20 - Southern Electricity 
                21 - SWALEC 
                22 - SWEB 
                23 - Yorkshire Electricity 
Meter Point ID Number
This is a unique number within the distribution area to identify the actual metering point.
Check Digit
This number is calculated from the Distributor ID and Meter Point ID Number to provide a check digit that other systems can use to validate the both numbers.