1Used to ask about a price or quantity ("how much?"). Usually written in kana.
この時計はいくらですか。
How much is this watch?
今月の家賃はいくら払えばいいですか。
How much should I pay for this month's rent?
子どもはお菓子にいくら使ったの？
How much did the child spend on snacks?
2Attached after a rounded number (especially an amount of money) to mean "and something more" or "-odd," as in 五千円いくら ("five thousand yen and change").
値段は五千円いくらだった。
The price was around 5,000 yen and change.
今年の売上は一億円いくらに達した。
This year's sales reached about 100 million yen and change.
その時計は二万円いくらで売られていた。
That watch was being sold for around 20,000 yen and change.
3An adverb used in the pattern いくら〜ても/いくら〜でも to mean "no matter how much" or "however much."
いくら頼んでも、彼は手伝ってくれない。
No matter how much I ask, he won't help.
いくら考えても答えが出ない。
No matter how much I think about it, I can't come up with an answer.
いくら忙しくても、休みは必要だ。
However busy you are, you need rest.