Will barbecue sauce come out of a white T-shirt?

Bleach

Yes

Its better to just buy a new shirt.

It will be hard for the barbeque to come off. You will see after you wash your shirt.

Depends on how long it was sitting on the shirt. If it was wiped off 30 minutes after it spilled on the shirt it might leave a permanent stain. If it was wiped off immediately then it just wash off in the washing machine.

When it's time for more formal attire, sure.

Lmao, dont come to YA they will tell you it will make your shirt flammable.

Been there, done that. Ketchup, French Dressing and Worcestershire sauce as well. That's hit or miss depending on how big it is, if it is cotton or a blend with polyester and how much/how long it was on there. First of all, do not use bleach directly and DO NOT SCRUB! Use a cotton ball or Q-tip . Over a folded paper towel or other absorbent material, try dabbing a big drop of detergent or pre-treatment on the spot and try to push the stain into the absorbent material under it then let sit for about fifteen or so minutes. Don't let it get dried out. Rinse area and repeat if necessary. If still some remains, white vinegar and baking soda can sometimes help. If that too fails to complete the job, try a little hydrogen peroxide, dab well let sit a couple of minutes, rinse well. You can also try Orange Clean/Oxy Clean or the stuff they call GOOP. Both great on grease and motor oil. Then wash shirt in hot water with the usual bleach. If none of that works, it may have to fade out on its own or you will have to wear it as is. I still have slight rusty colored spots on a couple of things, but so light now I don't even notice it. Oh, be sure to rinse well before using any other chemical type product applications. Some things with chemicals should not be mixed. Much like scrubbing, it might weaken the fabric. Be gentle. Good luck.

No, white clothing typically stain fast. You can try to bleach it but you will still see the spot unless it's really tiny.

No, you're gonna have to get more sauce.