How to invest/save my tax refund

[civil4life]

I will be receiving a substantial tax return this year.  This was unexpected due to some unanticipated deductions that significantly lowered by AGI.

I have a loan due it October that I will need to use the majority of the return for. 

The market is doing well and I doubt there would be a large financial crash prior to October.  Should I put it in the market?  If so what might you recommend?  I currently have my investment accounts in a targeted index fund with appr. 80/20 split.  Or should I play it safe and put it in a high interest savings account?

[DS]

Follow the same as if you received a paycheck or any other income.

Some reference: https://forum.mrmoneymustache.com/investor-alley/investment-order/msg1333153/#msg1333153

[Rob_bob]

Any money that you will need in Oct. should not be in the market.  High yield savings or a no penalty CD is what you need.

[Lady SA]

pay off the loan immediately, and invest the leftover like you would normally. A loan due in 9 months is not something you want to fuck around with, just get rid of it and move forward without having that hanging over your head.

Otherwise, if you don't want to pay off the loan yet (0% intro rate on a cc, maybe), put it in a high interest savings account until you need it. Or save half and invest half, whatever. But I wouldn't invest the whole thing, not when you'll need the full amount so soon.

What was your plan to pay off the loan before getting this unexpected windfall? Would you have been able to save enough cash yourself to pay it off by Oct?

[civil4life]

It is no interest until Oct. 22nd.  Loan for solar panel installation.

I would be paying the loan off with cash savings.

[JrBills5150]

You'd be much more upset by a 10% loss between now and October 22 than you would be happy with a 10% gain...put it in a CD

[Scandium]

I doubt there would be a large financial crash prior to October. 

How do you know this? Why is it any less likely to happen say this july, rather than next july?