You can change left, right, top, or bottom margins in a document by using the Page Setup dialog box in Microsoft Word. You can also use the Page Setup dialog box to set "mirror" margins so that inside and outside margins are the same width on the front and back of a double-sided page, and to set "gutter" margins on a bound document to add extra space to the side or top margin so that text isn't obscured by the binding.

To change margins

1. Position the cursor anywhere in the document to change margins in the entire document, or select text to apply changes to.
2. On the File menu, click Page Setup, and then click the Margins tab.
3. Enter new values in the Top, Bottom, Left, or Right boxes.
   To see how changes will affect the document, look at the sample page in the Preview box.
4. In the Apply to box, click the portion of the document you want to apply the settings to.
   You can apply changes to an entire document, a paragraph, or the current section. If you select text in the middle of a document, and change margins, then Word will create a new section if you have not already done so.

To set inside and outside margins on a double-sided document, select the Mirror margins check box in the Page Setup dialog box, and then enter values in the Inside and Outside boxes.

To set a gutter margin, enter a value in the Gutter box in the Page Setup dialog box. Word automatically inserts the gutter margin between the two pages on a double-sided document. For a single-sided document, click Left or Top under Gutter position.