Prices are linked to half hourly day-ahead wholesale prices. So yeah, they change daily.
Prices include VAT.
Standing charge is 22p per day.
Further details here:
https://octopus.energy/agile/
If you already have a smart meter, there are various third-party sites which can look at your usage and tell you what Agile would actually cost you. I use
Smart At Home. I just hop on and check the last 30 days every so often. If I'm still saving money vs Octopus Go and Bulb, I'll stick with Agile. If it becomes more expensive over an extended period, I'll switch away.
***No referrals***