It was noted here recently that the U.S. Postal Service is under instruction to forward federal tax forms without extra charge.

These instructions do not apply to state tax forms. When state tax forms need forwarding, somebody must pay a forwarding fee.

An explanation of the rules relating to state tax forms is now at hand from USPS Consumer Advocate Thomas W. Chadwick, who must surely be one of the most earnest civil servants in town.

Chadwick says tax forms are usually sent by third-class mail. "Normally, third-class mail is forwardable only when the addressee is willing to pay the additional forwarding fee. There is also another service for third-class mail; if the mailer guarantees return postage, then the item is forwarded and delivered if the addressee pays the additional postage. If the addressee refuses to pay the forwarding postage, or if the addressee cannot be found, the item is returned to the sender, who pays the additional postage.

"The exception provided the U.S. Internal Revenue Service from these general rules regarding third-class is permission to prepay the forwarding fee rather than to charge it to the addressee."

permission to prepay the forwarding fee? Did we read that correctly?

Yes, we did. The annual IRS tax form distribution is probably the largest and most comprehensive mailing by any federal agency or private organization, and it therefore lends itself rather well to statistical analysis.

The law requires that postage for federal agency mailings be paid through a reimbursement procedure. Because of this, federal mailers and the Postal Service have administrative procedures that "ensure an accurate accounting of the matter mailed and the postage required."

As a result of decades of "closely controlled and cooperative experience" in delivering those IRS tax forms, USPS and IRS have developed "reliable statistical procedures" for figuring out how much IRS owes for postage - "including the built-in forwarding charges."

Because of the singular nature of the IRS mailing and the accuracy of the statistical information, "it is administratively and economically feasible for the Postal Service to accommodate the IRS with this special feature, which we think is a convenience to federal taxpayers," says Chadwick. "However, because of the diversity of the 50 states and their mailings, it is not economically possible for the Postal Service to accommodate them in the same manner. We would have to develop 50 different systems for computing forwarding postage."

And as for that Virginia tax form for Charles Dent being "misdirected" to Wisconsin: It wasn't. "Believe it or not," says Chadwick, "all Virginia tax forms are printed and mailed from Green Bay." Did you know that?

Virginia supplies mailing labels to Moore Business Forms of Green Bay, which prints the forms and sends them out by third-class mail.

Using third-class mail saves the state a lot of money but requires Moore to sort its mailing by ZIP number before taking them to the post office.

This year approximately 4,000 of Virginia's mailing labels (Charles Dent's among them) carried no ZIP number, so they didn't qualify for third-class rates. They had to be sent first-class, and that's why they carried 35 cents in postage and were postmarked in Green Bay, not Richmond. Another mystery solved.

Now let me raise this question: Why should it be necessary for the Postal Service to charge each state the precise to-the-penny cost of forwarding tax forms?

Our congressmen give themselves free mailing privileges and extend that same courtesy to members of the armed services and others. Congress also gives big discounts to nonprofit groups. But it has little interest in keeping track of precisely how much it costs USPS to provide these services.

If Congress can be so charitable to foreign countries, and to itself, and to others, perhaps it could also provide harried taxpayers with the same service on state tax forms that they now receive on federal forms.

All that's required is a reasonable flat-sum appropriation to pay the Postal Service for forwarding state tax forms without extra charge.

In this era of revenue sharing, does it really make a big difference whether forwarding fees are paid by the states or by the federal government? The important thing here is not who pays but whether there will be quick and certain delivery of each taxpayer's forms.