The Citi Dividend 5% categories for the second quarter of 2023 being Gas and Home Improvement.
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Citi is different than the other cards in that you have a $6,000 annual cap rather than a $1,500 quarterly cap. Thus, you can get 5% back on up to $6,000 in this quarter, you can save the entire amount for a different quarter, or you can use part up each quarter. Hopefully most people took advantage of the categories last quarter.
Source: doctorofcredit.com