Why most MPAN guides get it wrong
Search "what is my MPAN" and you will find dozens of articles repeating the same line: "it is the 21-digit reference that identifies your electricity supply". That is true, and useless. The reference matters because every supplier's pricing engine reads the same 21 digits and uses them to decide whether you exist, in their world, as a customer they can sell to.
The number is split into two lines on your bill. The top line is metadata about your meter and your network section. The bottom line is the unique address of your supply point. The metadata is the interesting part: it is the silent filter behind every switching quote you have ever received.
In other words, your MPAN is not really a number; it is a profile. Understanding the profile is how you stop accepting whatever deal a comparison site happens to surface.
21
The full length of every valid UK MPAN
14
DNO network areas across Great Britain
Each with its own 2-digit Distributor ID
8
Profile Classes (00 to 08)
Decides which tariffs you can switch to
What your MPAN actually tells your supplier
Every MPAN follows the same fixed structure set by Elexon, the body that runs the electricity settlement system. It is printed on your bill in two rows underneath a large letter S. The S has no meaning beyond marking where to look. The full 21 digits break down as 8 digits on the top line and 13 digits on the bottom line. Here is a real, valid-looking example:
Example MPAN as printed on your bill
Marker only; the data is in the two rows below.
Top line (supply characteristics)
Bottom line (supply point address)
Two rows, five real segments. The top row never appears on a comparison site, but it controls what you can buy. The bottom row is what your supplier types into their address book when they accept you as a customer.
The five MPAN segments, and what each one means for you
Treat the breakdown below as a translation table. When a supplier quotes you a price, this is the information their pricing engine has already read.
Profile Class (2 digits): the tariff filter
The Profile Class is a 2-digit code that tells suppliers what kind of consumption pattern your meter is expected to follow. There are nine of them, numbered 00 to 08. For domestic customers, only two matter:
- 01 means domestic, single rate (one unit price all day);
- 02 means domestic, two-rate (Economy 7 or similar, with a cheaper night rate).
Codes 03 to 08 are for non-domestic supplies, ranging from small shops (03) up to large premises with maximum demand metering (08). Code 00 is reserved for half-hourly settled supplies, typically large commercial sites.
Insider tip: the Profile Class lockout. If a comparison site keeps showing you only a handful of expensive fixed tariffs while your neighbour sees many, check your Profile Class. A Class 02 supply forces the pricing engine to assume night usage; if you no longer use Economy 7 (the storage heaters were ripped out years ago), you are effectively locked out of the cheapest single-rate fixed deals. The fix is a Change of Measurement Class, requested through your supplier.
Meter Time-switch Code (3 digits): how your meter charges time
The MTC sits in the middle of the top line. It tells the industry which physical meter type sits at your address and, crucially, how many time-of-use registers it can read. A single-rate meter, a two-rate Economy 7 meter, and a smart meter all carry different MTC codes. If your meter is swapped (for example, a smart meter installed), the MTC changes, and a chain of downstream systems updates with it.
Line Loss Factor (3 digits): the network charge you never see
The Line Loss Factor accounts for the electricity that disappears as heat between the grid and your wall socket. It is a number applied to your network charges (and folded into your standing charge), not to the kWh you actually use. Two houses on opposite ends of the same town can sit on different LLF codes if they are fed from different substations.
Distributor ID (2 digits): which network owns the wires to your home
The first two digits of the bottom line are the Distribution Network Operator ID. There are 14 regions across Great Britain, each operated by one of six DNO companies. Your DNO is not your supplier; it owns the cables and the substation, and it is who you call when the power goes out. Common codes include 10 Eastern, 12 London, 14 Midlands, 22 South Western, and 23 Yorkshire. The full mapping is built into the decoder below.
Unique Identifier (10 digits) and Check Digit (1 digit): the actual address
The last eleven digits of the bottom line are the part that is unique to your supply point. The first ten identify the meter point itself; the eleventh is a check digit calculated from the preceding twelve digits of the bottom line (the Distributor ID plus the ten-digit identifier) using a weighted modulo-11 formula. Suppliers use it to spot typos before they accept a switch. If your check digit fails, your switch quote will be quietly rejected upstream, even if everything else looks right.
Where MPANs trip people up
The MPAN does its job quietly, until the day it does not. These are the four situations where things go wrong:
- Moving home. The new occupier inherits the property's MPAN, including its Profile Class. If the previous tenant had Economy 7 storage heaters and you do not, you can spend years on Class 02 paying a tariff designed for night-time loads;
- Dual-MPAN properties. Some homes have two MPANs feeding a single meter (typically a heating-only circuit plus a general supply) or two separate meters. Each MPAN carries its own standing charge, so a switch quote covering only one of them is incomplete;
- Profile Class lockout. As above, a stale Class 02 can hide the cheapest fixed deals on comparison sites;
- Mismatched DNO and LLF after a meter swap. Smart meter installs sometimes leave the LLF pointing at the old meter's network section. Suppliers then under or over-charge the network element of the standing charge until it is corrected.
All four are fixable, but only if you know to look. The decoder lower down on this page will flag the first three automatically.
How to find your MPAN and verify it is right
Your MPAN is printed on every electricity bill, usually in the top-left or bottom-right corner, underneath a large letter S followed by two rows of digits in seven small boxes. It is sometimes labelled Supply Number or S-Number. It is not on the meter itself.
If you have no bill (you have just moved in, for example), you can ask your DNO. To find the right DNO without knowing it, the Energy Networks Association postcode tool identifies it from your postcode.
To check the check digit by hand, multiply each of the first twelve digits of the bottom line by these weights, in order: 3, 5, 7, 13, 17, 19, 23, 29, 31, 37, 41, 43. Add the results, divide by 11, and take the remainder. The final digit of that remainder must match the printed check digit. If the remainder is 10, the MPAN is invalid. The decoder below runs the same calculation in real time as you type.
Decode your MPAN
Paste the 21 digits from your bill. We will parse each segment, look up your DNO and Profile Class, and verify the check digit in real time. Nothing is sent anywhere; the calculation runs entirely in your browser.
Spaces are ignored.
Top line: supply characteristics
Bottom line: supply point address
Plain-language verdict
Frequently asked questions
A small minority of properties have two MPANs because a separate circuit is metered independently. The most common case is a dedicated heating supply (storage heaters) feeding from one MPAN while general household consumption goes through another. Each MPAN carries its own standing charge, so a switch quote that covers only one is incomplete.
', ], [ 'title' => 'Can I change my Profile Class if I no longer need Economy 7?', 'content' => 'Yes. You can request a Change of Measurement Class through your supplier. If your meter is still a two-rate Economy 7 unit, the supplier will usually need to install a single-rate or smart meter first, then update the Profile Class to 01. After that, the cheap fixed tariffs that were hidden from you on comparison sites become available.
', ], [ 'title' => 'How do I find my MPAN if I have no bill?', 'content' => 'If you have just moved in and have no statement yet, contact the Distribution Network Operator for your postcode. The Energy Networks Association keeps a free postcode lookup that returns the right DNO. The DNO can share the MPAN for any supply point in its area.
', ], [ 'title' => 'How does the current Ofgem price cap relate to my MPAN?', 'content' => 'The cap itself does not depend on your MPAN, but the tariff that the cap is applied to does. For the period 1 April to 30 June 2026, a typical dual-fuel household on Direct Debit pays around £1,641 per year, at 24.67 p/kWh for electricity and a 57.21 p/day national average standing charge. The exact standing charge varies by Line Loss Factor and Distributor ID, both of which live inside your MPAN.
', ], ]" />