It’s seen as traditional to wear a hat for a wedding. However, it’s not always necessary, and you will often be left wondering whether you’ll look fussy or overdressed.
The Mother of the Bride is still usually expected to wear a hat. If your daughter is getting married in a traditional ceremony, it is probably safest to comply with this tradition. You can always remove your hat later in the day if you want to.
If you are just going to the evening reception as opposed to the whole ceremony and wedding breakfast, you probably won’t need an overly formal outfit and certainly won’t require a hat. Receptions tend to be like parties so wear something appropriate which you can dance in.
You might choose to wear a fascinator instead of a hat. This is a good compromise as it won’t look as formal, but it will still mean that you can wear something on your head if you prefer to. They’re a lot cheaper than hats and come in many different styles and colours.
That being said, if you would like to wear a hat, you should. It certainly won’t be frowned upon and a wedding is probably one of the few occasions when you can still wear a hat.