The Excel’s Month function can help you to extract the month form the date, and then sort them by month and year quickly. Please do as follows:

1. In the adjacent blank cell of the dates, for example the Cell C1, enter the formula =Month (B2), and then drag this cell's AutoFill Handle down to the range as you need. And the months have been extracted from the birthdays. See screenshot:

2. Keep selecting these months, and click Data > Sort Smallest to Largest or Sort Largest to Smallest.

3. In the opening Sort Warning dialog box, please check the Expand the selection option, and click the Sort button.

And now the dates have been sorted by the month only at once. And you can delete the new column with month as you need.

Sorting birthdays by month and day only, while ignoring the year, here is another formula can help you: =TEXT(B2,"MMDD"). Use this formula to get the month and day only. And then, sort the dates as normal. See screenshots:

Tired of using helper columns to sort your data in Excel? Look no further! With Kutools for Excel's Advanced Sort feature, you can effortlessly sort birthdays by month without the hassle of creating additional columns. Kutools for Excel can help you accomplish a variety of complex sorting tasks that are difficult to achieve with Excel's built-in features.

1. Select the list you want to sort the date by month and click Kutools Plus > Advanced Sort. See screenshot:

2. And then in the Advanced Sort dialog box, select the birthday column, and choose Month from the Sort On drop down list, then, choose the sort order, and click OK button. See screenshot:

And now you can see the birthdays have been sorted by month only. See screenshot:

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