Is it necessary to change budget every month?

You should change your budget since your life doesn't remain same in all the months. Some expenses don't change every month like house rent, tuition fees, etc. But your expenses on food, clothes, and entertainment change every month. You should change your budget plan accordingly. Change your budget plan as per your expenses. If you have an anniversary next month, then allocate extra funds for it.

Planning your budget is important as it helps in keeping track of your finance. Keeping a budget for every month is good. It is not necessary that every month has the same budget plan. Expenses may change according to seasons, one's need also. So, having a monthly budget plan is important.

Yes, you need to revisit your budget every month to review whether or not it is working. If you are following a budget to set aside money, then you need to find out extra cost and eliminate that and readjust your budget. It will help you to save money. To follow a budget, you need to have a fix income source.