​​Combined return filers must properly report estimated payments in order for the department to properly apply them.

Only the "designated agent" corporation should be making estimated payments on behalf of all corporations in the combined group. The "designated agent" is the corporation under whose name the group files its Wisconsin combined Form 4. (The designated agent is often the parent company but can be any company in the combined group).

The department is aware that in many combined groups, corporations other than the designated agent may have made their own estimated payments in 2009. Also, some members may have had carryovers of estimated payments from 2008 available to use in 2009.

If any member of the group other than the designated agent made estimated payments to apply to the 2009 return (or had carryovers available to apply), report those payments and carryovers on Part IV of that corporation's Form 4M

Also, Form 4M is a critical component to the combined return because it serves many other purposes. Here are some reminders about Form 4M:

• A combined return must have a Form 4M for each member of the combined group. The number of Form 4Ms included in the return must equal the number of corporations in the group as reported on Form 4, item E.
• The amounts in Part I of Form 4M for each member must add up to the amount on the corresponding line of the group's Form 4.

Also, remember that combined returns must be filed electronically (see s. Tax 2.67(2)(b), Wisconsin Administrative Code). If electronic filing creates an undue hardship, you must obtain a waiver from electronic filing. See this previous article​ for more information.

September 27, 2010