Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

Why would you elect to apply a refund to next year's tax bill?
The refund may offset your liability for the next year, especially if you are a Schedule "C" filer.  By having your refund applied to the coming year's taxes you are building a 'protection' against a potentially high liability if you were planning to sell a building that was a commercial building and would have Capital Gains. Or you sold stock at a profit that would also put you in the Capital Gain area.  You won a large sum in a lottery, the refund could cushion a bit of the tax. In short, if you think you will have a tax liability in the current year then on the tax return you are filing for the year that just past, it may be to your benefit to apply the refund.  If you owe money  from a prior year, the refund will not be sent to you so you will not be able to roll it forward.    One specific example is you did qualify in the prior year for the ACA.  If in the year you are currently in- before you file your taxes-- you realize that you will have to pay at the end of the current year, then assigning your refund will pay part or all of the liability. Keep in mind that the 'tax' imposed due to ACA is only collected from your refunds.  If you keep having a liability to pay  or have no refunds due to you, the liability is not collected from you.