under the table

under the table (something not recorded, not truly official, kept secret) — неофициальная зарплата, черная

Example: Example: "Since Anna was an illegal immigrant from Cuba, she could only receive money under the table from her employers."

(This is usually used when speaking about employment and money.)

If you wanted to say someone was not receiving money under the table, you would probably just go ahead and say, "She is a legal worker." or something to that effect. I can't think of any idioms to describe that.

see also
[under the counter]
[on the QT]
[keep a low profile]
[черный нал]