Business Energy Glossary
What is a Meter Asset Manager (MAM)?
A Meter Asset Manager, almost always shortened to MAM, is the UK industry party responsible for installing, maintaining, replacing, and removing gas meters. The MAM is the gas equivalent of the Meter Operator (MOP) on the electricity side. Most UK business gas customers are unaware of their MAM because the supplier appoints one as part of the supply contract. Larger customers can contract directly with a MAM separately from the energy supply, choosing the MAM based on service and price.
For smaller gas supplies the MAM is invisible operationally and the cost is bundled into the standing charge. For larger gas users, particularly daily metered sites, the MAM relationship matters because the meter equipment is complex and the fees are material.
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The role of the MAM
A Meter Asset Manager (MAM) is the accredited company that installs, maintains and replaces gas meters on behalf of the supplier or customer. Its fee is usually built into your gas standing charge, though larger sites can contract with a MAM directly.
For the full explanation, see Understanding How Business Gas Meters Work.
The MAM is responsible for everything physical relating to the gas meter:
- Installing the meter when the supply is energised.
- Maintaining the meter through its operating life.
- Replacing the meter at end of life or when faulty.
- Removing the meter when the supply is disconnected.
- For DM sites: installing and maintaining the data logger and communications equipment.
The MAM holds the technical relationship with the meter for data purposes on DM sites. On NDM and smart meter sites, the data flow is simpler but the MAM remains responsible for the physical equipment.
How a MAM is appointed
Two appointment models:
- Supplier-appointed. The energy supplier has framework contracts with MAMs and appoints one as part of the supply contract. The MAM fee is bundled into the standing charge or unit rate.
- Customer-appointed. Larger gas customers contract directly with a MAM separately from the supplier. The MAM fee is invoiced separately. The customer can choose the MAM based on service quality and price.
Customer-appointed MAMs typically come into play above the mandatory daily metered threshold (AQ above 58,600,000 kWh a year).
MAM fees
Annual fees vary by meter type and complexity:
| Meter type | Typical annual MAM fee |
|---|---|
| Domestic-type diaphragm (U6) | £20 to £40 |
| Mid-commercial diaphragm (U16, U25) | £50 to £120 |
| Larger commercial (U40-U100) | £150 to £400 |
| Industrial (rotary, turbine) | £400 to £1,500 |
| DM site with data logger | £800 to £3,000 |
Customer-appointed MAMs
For larger gas users, customer-appointed MAM contracts may reduce metering costs against supplier-bundled rates. The trade-offs:
- Lower cost. Direct contract pricing without supplier mark-up.
- Service choice. Choose MAM based on service capability.
- Administrative complexity. Two separate invoices (supply from supplier, metering from MAM) instead of one.
- Coordination. Customer manages MAM service relationship directly.
For multi-site gas portfolios above 10 GWh per year of total consumption, direct MAM contracts are usually worthwhile.
MAM vs MOP
The two roles are equivalent across fuels:
| Function | MAM (gas) | MOP (electricity) |
|---|---|---|
| Installs meters | Yes | Yes |
| Maintains meters | Yes | Yes |
| Replaces meters at end of life | Yes | Yes |
| Manages data communications | For DM sites | For HH sites |
| Customer or supplier appointed | Both possible | Both possible |
Changing MAM
For customer-appointed MAMs, switching is administrative:
- Sign new contract with the preferred MAM.
- Notify the existing MAM of the termination date.
- Transfer operational responsibility on the agreed date.
- Tell your supplier, which updates the central records held by Xoserve.
The physical meter does not change. The MAM responsibility for that meter transfers from one party to another.
a Meter Asset Manager (MAM) FAQs
What is a Meter Asset Manager?
The UK industry party responsible for installing, maintaining, replacing, and removing gas meters. The MAM is the gas equivalent of the Meter Operator (MOP) on the electricity side.
Who appoints the MAM?
For most small and mid-market business customers, the supplier appoints the MAM as part of the supply contract. Larger gas customers can contract directly with a MAM separately from the supplier.
How much does a MAM cost?
Annual fees range from £20 to £40 for small diaphragm meters up to £800 to £3,000 for daily metered sites with data loggers. The fee depends on meter type, size, and equipment complexity.
Should I appoint my own MAM?
For larger gas portfolios (typically above 10 GWh per year total consumption), customer-appointed MAM contracts may reduce metering costs against supplier-bundled rates. For smaller sites, supplier-bundled is usually simpler.
What is the difference between MAM and MOP?
MAM is the gas equivalent role; MOP is the electricity equivalent. Both install and maintain meters; MAM works on gas meters, MOP works on electricity meters.
Can I change my MAM?
Yes, on customer-appointed contracts. Sign with the new MAM, notify the existing MAM of the termination date, and the transfer is administrative. The physical meter does not change.
Does the MAM fee appear on my bill?
On supplier-bundled arrangements, no; the fee is included in the standing charge or unit rate. On customer-appointed arrangements, the MAM invoices separately from the supplier.
Who installs my smart gas meter, the supplier or the MAM?
The MAM, on instruction from the supplier. The supplier arranges the installation; the MAM carries out the physical work via a registered Gas Safe engineer.