The most common and most likely answer to this crossword clue is the 8 letter word RECEIPTS
I've seen this crossword clue in The Guardian
R
E
C
E
I
P
T
S
Buddy explains!
The straight part
We know that "income" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case income = receipts.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RECEIPTS mean?
RECEIPTS noun- The act of receiving, or the fact of having been received.
- The fact of having received a blow, injury etc.
- (in the plural) A quantity or amount received; takings.
- A written acknowledgment that a specified article or sum of money has been received.
- (usually in the plural) (A piece of) evidence, documentation, etc. to prove one's past actions, accomplishments, etc.
- (usually in the plural, by extension) (A piece of) evidence (e.g. documentation or screen captures) of past wrongdoing or problematic behavior or statements.
- (archaic in New England and rural US since end of 20th century, elsewhere since middle of 20th century) A recipe, instructions, prescription.
- A receptacle.
- A revenue office.
- Reception, as an act of hospitality.
- Capability of receiving; capacity.
- A recess; a retired place.
- To give or write a receipt (for something).
- To put a receipt on, as by writing or stamping; to mark a bill as having been paid.