All brides and grooms start out with what they believe is a "realistic" wedding budget. If you're working with a wedding planner, he or she should be able to help you with the numbers and create a guesstimate of what everything will cost when you add it all up and include gratuities.
With that said, only you can blow your budget. Your wedding planner isn't the one who is actually spending your money—you are! You will be given options and you will make decisions and sign contracts. End of day, you were the one who couldn't live without the sparkler tunnel or the second wedding gown.
Here's a list of the top five things that will cause you to blow your wedding budget:
Choosing the top-level bar at all of your events.
Do you really need to serve Bombay Sapphire gin and Belvedere vodka? After the first few drinks, it doesn't even matter what kind of booze it is — they'll keep on drinking. Serving a lower level of bar doesn't make you look cheap — you're still providing an open bar for quite a long period of time.
Overdoing it with flowers and décor
Are you getting married in a beautiful venue or outdoor location? If the room is already exquisite or you're already in the midst of an amazing garden, don't try to gild the lily. Less is often more in this situation.
Extending your wedding reception to run all night
Every additional hour costs you more money on everything. None of the event staff can begin breakdown or cleanup until your wedding is over. So you have to pay to keep the kitchen staff, the service staff, security, the wedding planners, the music and maybe even your photographer if you really want those crazy late-night shots. This can add on megabucks to your budget.
Having a huge wedding party
Do you really need eight bridesmaids, four junior bridesmaids, and three flower girls? The cost of the flowers for the bridal party alone will go into the thousands by the time you're done. Plus, don't forget you must buy gifts!
Trying to provide transportation for everyone
It's a smart (and safe) idea to have a bus on hand late night to get guests back to the hotel safely, but don't feel like it's your responsibility to get your guests to and from your actual wedding and reception and their accommodations. Half of the time, they'd rather drive their own rental cars and have control of how long they stay. They don't like feeling stuck. Unless the hotel has a free shuttle on hand, don't try to coordinate everybody.