To merge cells in Excel, select the cells you want to combine, then on the Home tab click Merge & Center. That is the quick answer, but Excel actually offers four different merge behaviors, and choosing the wrong one can silently delete data. Here is how each works and when to use it.

The fast way: Merge & Center

  1. Select the two or more cells you want to merge — for example, drag across A1:C1 to span a title over three columns.
  2. Go to the Home tab on the ribbon.
  3. In the Alignment group, click Merge & Center.

The selected cells become one, and whatever was in the top-left cell is centered inside it. This is the go-to choice for a heading that sits above several columns. The steps are the same in Excel for Windows, Mac, and the Microsoft 365 web app, though on the web the button sits in the same Home tab with a slightly simpler menu.

The data caveat you must know

Here is the single most important thing about merging: Excel keeps only the value in the upper-left cell and throws the rest away. If A1 says “Sales”, B1 says “Q1”, and C1 says “Q2”, merging them leaves you with just “Sales”. Excel does warn you — a dialog says the merge will keep only the upper-left value — but it is easy to click through without reading. Before you merge, make sure the cells you are combining are empty or contain only the one value you want to keep.

All four merge options

Click the small arrow next to the Merge & Center button to see the full menu:

  • Merge & Center — combines the selected cells into one and centers the content.
  • Merge Across — merges each row in your selection separately. Select A1:C3 and choose this, and you get three merged cells (A1:C1, A2:C2, A3:C3), not one big block. Great for repeating row labels.
  • Merge Cells — combines the cells into one but leaves the text alignment untouched (no automatic centering).
  • Unmerge Cells — splits a merged cell back into individual cells, returning content to the upper-left position.

The better alternative: Center Across Selection

Merging looks tidy but causes real problems: you cannot sort merged rows cleanly, some formulas and references misbehave, and copy-paste gets awkward. For a centered heading, professionals often avoid merging entirely and use Center Across Selection instead, which centers text across cells without combining them:

  1. Type your heading in the left-most cell and select across the range you want it centered over.
  2. Press Ctrl+1 (or right-click and choose Format Cells).
  3. Open the Alignment tab.
  4. Under Horizontal, choose Center Across Selection, then click OK.

Visually it looks identical to a merged heading, but every cell stays independent — so sorting, filtering, and formulas keep working. If you build spreadsheets other people will edit, this is the safer habit.

How to unmerge cells

If you inherit a sheet full of merged cells, you can undo them:

  1. Select the merged cell (or an entire range, or the whole sheet with Ctrl+A).
  2. On the Home tab, click the arrow next to Merge & Center.
  3. Choose Unmerge Cells.

The content lands back in the top-left cell of each formerly merged block. This is often the first step in cleaning up a messy spreadsheet before you sort or analyze it. A quick way to find every merged cell first: open Find & Select > Find, click Format, tick Merge cells under the Alignment tab, and search — Excel highlights them all so nothing hides.

Common problems merged cells cause

It is worth understanding why spreadsheet professionals treat merging with caution, because the side effects are not obvious until they bite:

  • Sorting breaks. Try to sort a range that contains merged cells and Excel throws the error “This operation requires the merged cells to be identically sized.” You have to unmerge before you can sort.
  • Selection behaves oddly. Selecting a single column can drag in extra rows because a merged cell spans them.
  • Formulas can miss data. A reference to a merged block only sees the top-left value, which can quietly throw off counts and lookups.
  • Copy and paste gets awkward. Pasting over or around merged cells often triggers errors or reshapes your data unexpectedly.

None of this means you should never merge — for a static report or a printout, a merged title is perfectly fine. Just avoid merging anywhere in the actual data grid you plan to sort, filter, or calculate on.

Why the button is sometimes grayed out

If Merge & Center is disabled, the usual culprit is an Excel Table — merging is not allowed inside one. Convert the table to a normal range (Table Design > Convert to Range) and the option returns. The button is also inactive while you are actively editing a cell; press Enter or Escape first.

Bottom line

Merging is perfect for simple titles and printed reports, as long as you remember it keeps only the top-left value. For anything you will sort, filter, or run formulas over, reach for Center Across Selection instead. Both give you a clean, centered look — but only one keeps your data intact.

Once your sheet looks the way you want, you will often need to share it. If you are sending it as an image, our guide to taking a screenshot on a Mac shows the quickest way to capture just the range that matters. And if it is going out by email, you can schedule the email in Gmail so the report lands in your colleague’s inbox first thing in the morning rather than at midnight.