Christmas Bonus

[jamesbrown]

I'd parade around the car park naked, letting the client whip me whilst shouting "I'm a disguised permie, come and get my big boys at HMRC!" if my client gave me £5K for no reason.

Yeah, but you'd do that for a can of Diamond White.

[Brussels Slumdog]

Invoice them for a Stand by fee. You couldn't go away for weekends as you were on call

[jamesbrown]

Invoice them for a Stand by fee. You couldn't go away for weekends as you were on call

If you're going to lie, you may as well back-date an invoice for ordinary services, not actually delivered. It's missing the point entirely. It's asking your client to be complicit in that lie and, chances are, they won't remember the story in a few years.

No, the best you can do is to not draw attention to it too much, but to otherwise accept the bonus for what it is. As others have pointed out, this would be a point of contention with HMRC, but it's unlikely to prove decisive, especially as the OP doesn't operate in a borderline way (based on earlier posts). Conversely, getting caught in a lie could prove decisive.

[JB3000]

I wouldn't try to dress this up as something it isn't.

Indeed, deliberate and concealed errors are pretty harsh:

CH82470 - Penalties for Inaccuracies: Calculating the Penalty: Penalty reductions for quality of disclosure: Maximum and minimum penalties for each type of behaviour