What Is MHHS?

MHHS (Market-Wide Half-Hourly Settlement) is Ofgem’s national project to make every electricity meter half-hourly settled — not just the big ones.

It means every customer’s consumption will eventually be recorded every 30 minutes instead of estimated once a year.
✅ More accurate billing.
✅ Fewer disputes.
✅ Dynamic tariffs later down the line.

Roll-out runs 2026 → 2028, with supplier systems already shifting in the background.

⚡ What’s Changing Right Now

Suppliers are beginning to change topline structures from using MTC (Meter Timeswitch Class) to SSC (Standard Settlement Configuration) codes.

Example:

Old MTC format: 03801201  
New SSC format: 030151201

(i.e. the old “801” becomes “0151”)

Nothing to panic about — the change simply future-proofs meters for half-hourly settlement.
Your BOS Broker Tools already handles this automatically.

During the transition on pricebooks, you must enter either MTC or SSC — never both. If both are entered, suppliers will invalidate the topline and the field will appear blank or unsupported until mapping is complete.

⚠️ Why It Matters

• Some portals and toplines now expect SSC instead of MTC.

• Submitting the wrong format = auto-reject.

• Smart-metering and half-hourly settlement are gradually merging — suppliers are tightening validation.

📡 Smart Meters – No More Hiding

In line with MHHS, smart-meter upgrades are being rolled out nationwide.
Why? Because half-hourly settlement requires half-hourly data, and that only comes from smart meters.

So yes — soon, smart metering will be mandatory for all business sites.  
Mr Singh’s Stores can’t hide behind the old Ferranti dial meter forever.

Suppliers will contact customers directly to arrange upgrades — brokers can’t block it, delay it, or “opt out.”

⚠️ Important: Those customers who drag their feet on smart upgrades will almost certainly face:

• Higher contract prices, as non-smart meters will eventually be classed as higher-running cost; and

• Commission delays, because D19 data-flow transfers (the half-hourly data handshake between supplier and agent) can’t complete until the new meter is live and reporting.

Translation for the slow learners:
No smart meter = no data = no D19 = no commission.

✅ What You Should Do Now

1️⃣ Always use the latest LOA (available on Dropbox) — it already supports MTC + SSC topline entry.
2️⃣ Check the latest bill or use Broker Tools to confirm the profile class / SSC before submission. (*Credit apply for look ups)
3️⃣ Stay tuned for Topline updates — we’ll post new formats and data-field changes in advance.

⚙️ Supplier Impact (In Simple Terms)

So in short:
👉 Valda, BGB & Smartest = HH-only.
👉 EDF, E.ON & SP = still fine for MMHS (submit as normal with SSC).

💬 Q & A (Because Someone Will Ask Anyway)

Q: Do I need a new template for SSC toplines?
A: No — the new LOA and Broker Tools handle it automatically.

Q: Will rates change?
A: Eventually yes — expect more time-of-use tariffs once HH data flows start fully.

Q: Do I still need to submit dual MPANs together?
A: Yes. MHHS doesn’t magically fix related-meter stupidity.

Q: Can I ignore all this and hope it goes away?
A: No. 2028 will arrive whether you read this or not.

Q: Can I WhatsApp Arpit to ask if MHHS can be stopped because Rita’s Curry House doesn’t want a smart meter?
A: No. Ofgem doesn’t take WhatsApps.

Summary

MHHS = industry upgrade, not optional.
SSC codes are replacing MTC in toplines now — use Broker Tools and the latest LOA to stay compliant.
Smart meters are mandatory and directly linked to commission timing — the sooner customers upgrade, the smoother their switch (and your payment).