I am trying to remove a toilet and seal the sewer line so the bathroom can be used for storage. I know how to remove the toilet and cap the supply line but don't know what
To do about the open sewer line.

Will this be short term, long term or premanent?

You can use Test Plug. Insert the plug into the toilet opening and tighten the handle. If can be always removed if you decide to turn your storage room back into fully functional bathroom.

Probably for several years, but would like to have the option to re-install toilet.

OK, several years sounds long term but not permanent. Milo's plug could do that and can always be shifted or reinserted if a problem arose. If you want it flush I'd stuff an old towel soaked in corn oil down into the pipe to block it a few inches below flush and then fill the rest with mortar. You will have a flush surface with no trip hazard and the mortar can be popped out fairly easy when you are ready.

Permanent.

Actually, Milos plug is what is in it now. It has worked great, but I wanted to make it flush.

Actually, Milos plug is what is in it now. It has worked great, but I wanted to make it flush.


They actually make a plug that is flush with the floor. Same principle though but w/o that protruding square. It has a slot. I am not sure whether HD or Lowe's carries these. You would probably have to go to more professional supply house. There is also another plug, called "Knocked Out Plug". It glues directly over the top of the toilet inlet. Later, you just knock it out if needed. But this one fits only over ABS or PVC inlet.

Ballengerb1's advice ( concrete poured into the pipe ) is also an option to consider. It may be the most economical way of sealing it off.

Great... That's an option I can look into.

I'm looking for permanently remove an old toilet and to seal the sewer line. I've heard there are "Test Plugs" that work permanently. Can you tell me if these work, if so, where to find them?

Thanks!! :)