Excel 2007 : Summing up different dollar amounts for duplicate rows

Hi Guys,
I just found this forum and its great from what Ive been reading but i couldn't find any topic on my problem.

I work for a collection agency and i just got a spreadsheet that has over 5600 rows with the same account numbers but different amounts that the person would owe. I am trying to combine all rows with the same account number and then sum up the balance but they are all different. one person could have 6 rows with different balances and the other could have 2 rows with different balances and have same account number. I actually just spent the weekend inserting a line under every row with duplicate account numbers and then doing a sum formula by highlighting the amounts based on the same account number. but now the balances are way off. I am about to pull my hair out because that means i did something wrong and would have to go through and manually look at each account again which will take an eternity. Here is how it is


A B
Acct# DollarAmount
1234 100.00
1234 200.00
1234 300.00
2345 150.00
2345 200.00

I would like it to look like this

A B
Acct# DollarAmount
1234 600.00
2345 350.00

I am not new to excel but am still learning how to use it better. But i cant find anything on the internet to help and this forum seemed great for my case. If anybody knows how to solve this i would be EXTREMELY grateful for anybodies help.

Give the SUMIF function a try.

Or create a Pivot Table from the data.

If that takes care of your need, please click EDIT in your original post, click GO ADVANCED and set the PREFIX box to SOLVED.