My practice didn't include estate tax returns but it did include working with many very large corporate tax returns. I'm not sure if those can be filed electronically or not these days but no matter.

The most important thing in submitting a large filing is that the pages be bound very securely. I most often saw two different methods - long round-head paper fasteners (we called them "spikes") that were passed through a punched hole in the upper left corner of each page and then spread at the top to make it secure or bound booklets that had either plastic or wire binding on the side. Side bindings like these can be very large. Also, occasionally, the kind of double flat spikes (very long) that go through two holes at the top center edge of the pages, then with a plate put through the spikes to hold the pages snug, used for manila files. Don't use staples.

You can have binding done at a Fed Ex office (the former Kinkos). If doing that, you need to make sure the sequence of the pages isn't lost. Multiple parts to one filing, if clearly labeled, are absolutely not a problem. You know the drill, binder 1 of 4, 2 of 4, etc. Remember that many duplicate copies are required for all those who need it. I don't know, maybe 5 or more?

Then, as far as sending is concerned, I think I'd probably put them it into a Post Office Priority Mail Express box and use the normal IRS address specified for the Form 706.

600 pages suggests a good sized estate. I'm sorry for the decedent but it's a good client to have for the CPAs and lawyers. Good luck.

THANK YOU ELMER!!!

In my past, if I were sending forms to the IRS, I would have a footer that included the tax year, form number, identifying number for the company/person and the page number sequence (x of y). This way, it they get unbound or somehow damaged, they can get reassembled.

Mind you this was pre-electronic filing and for corporate returns.

We are a nosey bunch aren't we.

Why does someone want to talk to Elmer, what did he do wrong (or right), what do they want......

I spent my professional career in a small corner of this field, something I think I've mentioned without that much specificity a few times over the years.

Oh, and for dees - you've outed my secret way of obtaining insights and authoritative information on a wide variety of topics. But I'll comment that I don't think returns done by the software professionals used had sequential page numbers (my firm used what was called the Fast Tax Go System starting > 35 years ago) but I don't remember. But by then, I was at a point in my career that I was managing others and not doing actual hand's on return preparation work myself.