Martin Lewis: Which analyst firms give the best Price Cap predictions?

I used to solely & loudly use the excellent Cornwall Insight, so much so it probably helped build their brand, leading to many generalists treating it as gospel. Yet I moved on from it Autumn 2024 for two reasons...

1) Cornwall substantially reduced the frequency of its public predictions (as its valuable commercial data for it). It now only updates three times a quarter, so it can be a month out of date.

2) Three big energy firms started making public their own predictions and they update it every week, and as things change rapidly intra-week, the latest predictions are very important. As the Price Cap moves every three months, when you do an energy comparison what its predicted to be in future has a material impact on the size (and whether there’ll be) savings.

My solution was to create an MSE (mean) average of the three energy firms weekly predictions, and now I use that in my main communication (though our Cheap Energy Club sticks with just EDF’s predictions as it, uniquely, provides us with regional predictions and we want to try and make it as bespoke as possible within a comparison)

I've just asked my team, to use the benefit of hindsight and see how it all stacks up compared to the final Price Cap for each quarter. You'll see the results in the table below (I breathed a sigh of relief that the MSE average seems to be doing well).

PS. The table only looks at the final prediction each firm gives just before Price Cap announcement. This is arguably the easiest one to do as it is done after the close of the three month Price Cap Assessment period.

As the Price Cap is based primarily as a published algorithm relying on wholesale rates they all should be close, the variance is due to what they assume Ofgem will tweak.