Lookup

[swgrinder]

If I have an excel sheet with account numbers in column A, and amounts income and B. How can I add up amounts in column B based on an account number from column A?

 

[ajm]

use sumif formula

 

[myall_blues]

Here is an example using SUMIFS.
If you have difficulty for your specific circumstances then post a data example with a description of what you would like the result to look like,

Book1
	A	B	C	D	E
1	AC No	Amount		AC No	Total
2	0002	583.94		0001	3400.07
3	0003	725.28		0002	3363.4
4	0001	530.37		0003	2993.67
5	0002	385.26
6	0001	627.56
7	0003	303.06
8	0003	129.12
9	0001	724.45
10	0003	820.72
11	0002	396.71
12	0003	275.57
13	0001	654.86
14	0002	497.98
15	0003	739.92
16	0001	633.53
17	0002	794.8
18	0001	229.3
19	0002	704.71
Sheet1

Cell Formulas
Range	Formula
D2:D4	D2	=SORT(UNIQUE(A2:A19))
E2:E4	E2	=SUMIFS($B$2:$B$19,$A$2:$A$19,$D2)
Dynamic array formulas.