The new system is not even in place yet for broadband, but we had our first PSTN slamming today. In theory the PSTN side has been in place for some time, but it was very rare and we had a much less automated system in place before now. The new migration process means we have integrated our automated systems for PSTN lines as well as broadband.

Some other telco was trying to take over one of the PSTN lines that was part of an Office::1 installation. Our new system alerted the end user by email to their accounts and technical contacts and also texted them.

Unusually, it also alerted our sales staff as it is an Office::1 line, and transferring or ceasing one part of an Office::1 line is suspicious. The system has a few safeguards in place to try and pick up things like this.

Office::1 is a package of two or three PSTN and broadband lines with a FireBrick and optional 3G fallback providing a bonded and monitored service. Ceasing or transferring just one part of that service makes no sense, so will almost always be a mistake or slamming.

Needless to say the customer was pleased to be advised, and quick to confirm that he had not authorised a transfer.

Now we await our first broadband slamming - something that simply could not happen with MACs. Our what joy.

P.S. As someone asked on twitter, yes, you can pre-emptively tell us you are not planning to transfer so we reject a request (anti-slamming). It is on the control pages for your line.


  1. I'm Ofcom have thought of this possibility and have a way of reporting "slammed" lines for investigation of providers and will take action quite promptly to prevent a big issue arising in the future.... I also live in Azeroth.

    1. Except OFCOM have not defined cancel codes for *legitimate* cancellations - e.g. "End User is a company of over 10 staff" and so cannot tell legitimate cancellations from slamming and abuse. Well done OFCOM!

  2. What information do you get when a line is being slammed - just a cease notification, or do you get told who's trying to acquire it as well?

    My grandfather got talked into switching to some random cold-calling outfit earlier this year - maybe not quite "slamming" as such, but very dodgy. I'm not entirely certain, but it sounded like the same bunch that got me at work once, claiming to be "working with BT" (well, sort of, they're Openreach WLR3 resellers) and other vague assertions of legitimacy to get me on a 3 year contract where the price explodes after the first six months.

    I rather like A&A's anti-slamming facility, and activated it in Clueless as soon as I knew it was there. Is there some provision in case other ISPs abuse that sort of system, though, in the same way some would make it very hard to get a MAC in the past?

    1. Indeed, and I think OFCOM have concerns over it. As you saw, we have made it a very clear statement by the customer that we keep on record and very simple to turn off, but I expect other ISPs could simply reject migrates and abuse the system. One issue is the large companies (>10 staff) for which the whole system does not apply.

  3. In case of (attempted) slamming, any idea if this is a criminal offence or could only be reported to ofcom and finish in a black hole?

    1. I am not aware of any case law on this, but slamming sounds like fraud by representation to me:



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