Anything under 200 I leave them, if it's the end of the day and i'm genuinely not hungry then I don't see the point in eating something for the sake of filling them up. I tend to view calories as cumulative, so I generally don't pay too much attention if I go over one day or under the next, so long as it's never by silly amounts and I don't start using it as an excuse to routinely "bank" calories in order to have a binge session at the end of the week then it's all good.
Really it's whatever suits. I prefer to treat each day individually in order to achieve a weekly goal, if I over/under eat a line is drawn and then the next day is new and sparkly.