Most likely a SCAM.

Received a missed call from this number claiming to be from Citibank regarding a security concern. I tried calling back (which wasn't a smart move) and number was engaged. I then called the actual Citibank number on the back of my card and spoke with customer service who checked my account and said there was no record of me having been contacted earlier by Citibank. He also said security alerts are generally sent by SMS and to never give out personal info to anyone claiming to be Citibank over the phone (common sense but sometimes we get caught up and forget).

I have a feeling the comments on here claiming that this number is legitimate is left by the scammers themselves.

It's legitimate. Card security querying an unauthorized overseas transaction.

Stop lying, its a scam and you know it. No matter how many times you get your scamming friends to vote this as helpful its not fooling anyone.

Said they were from Citibank Credit Card Centre and there was suspicious activity on my wife's credit card. Tried to call them back and message returned "Number is not connected"

virgin money because I submitted an CC application

I received a call from this number on both my mobile and landline and a text message on my mobile. I didn't answer either but called Citibank on their public number to enquire. It is a legitimate Citbank number (credit dad fraud section). They called to report three fraudulent transactions on my credit card but I had already seen them and reported them to Citibank who had already tagged them as suspicious. Well done Citibank but it's just sad that we are all so suspicious of any phone calls now.

Caller: Coles Mastercard

I believe this is a legitimate call, Citibank own Coles Mastercard - (They purchased the Coles Credit Card Portfolio from Wesfarmers Finance in 2018). I rang Coles Mastercard a few days ago to make sure they had my correct address as my card is due to expire soon. They have a promotion at the moment where you can roll up to X amount into 60 months of repayments at a lesser interest rate - the lady on the phone pressured me about it so i said to call me back at a later date as i was at work. i assume this is why they are calling (they left a message saying they were from Coles Mastercard.) I rarely answer unknown calls due to scammers but i do believe this is a legitimate number as it is registered as a fixed finance number if you look it up.

it's great that so many people are suspicious now. If ever in doubt, don't answer or hang up & call the institution back they claimed they were from. all calls are logged.

it is a legitimate call from Citibank.

I got a call from this number. I had applied for a Qantas credit card which Citibank is the issuer of. The caller knew the details I had posted on my application and didn't ask for any personal information. She just wanted to follow up on some information I had provided and I got a text from Qantas 5 minutes afterwards advising my credit card application was successful.

Said they were from Citibank Credit card and needed the 3 digit number on back of card. I was busy and said I'd call back to tell them to stop scamming but "number not connected".

Picked up call from this number at 4th attempt. Said to be Citibank and advised internet banking attempted hack. They offered to reset or to call 132484 general number (back of debit card) which I did. I believe it is a valid number for Citi but recommend you hang up and call the contact centre as a precaution

claimed they were from the Bank of QLD. I spent ages trying to connect but no answer. I spent hours checking my accounts and yet all is in order. I am very nervous about their suspect behaviour.

Caller: Bank security - Virgin Money Visa

This is not a scam.
Evidently this is an extension for a bank security centre service. It must cover a number of credit card services.
I tried to make a legitimate Virgin Money Visa transaction but it looked suspicious to the bank so my card was blocked. I called the card centre who unblocked my card but they must have advised the security service. The next day I had a call from this number and they said it was security following up on the transaction and to confirm my card had not been scammed.
What made it more suspicious was that I was cut off and the call ended abruptly. When I tried to call the number back a voice recording said if I had an application?? the office was closed and to call back during office hours. I called the number on the back of my Visa card and the operator said that the call was a legitimate call from the security centre.
I suggested to them that the security person could have been more careful in their dealings and being a bit more secure with their call and identification process. I also told them a lot more people are being confused by calls from this number, hence the number of complaints on this website.

Scam, I applied for a credit card through Suncorp. They contacted saying they needed more info for application. I answered 2 questions then thought this is suspicious so I said to the guy on the phone I'd call them back through the number on application- he said to call the 1300 number others have mentioned. But I called the number on the application for suncorp spoke to a Australian there and they said there's no calls to my number from them so 100% a scam..

Caller: Don't know

Recorded message reported of unusual activity on my account & advised me to call Virgin credit card on 1300 771 634. I logged on to virgin cc website & this isn't the number listed for them. Also logged on to my account & there is no unusual activity

Caller: They claimed Diners card

I got a call from this number today claiming to be diners club. I’ve never had a diners club card. Scammer.

Left a voicemail saying they were from Diners card security and called in regards to some suspicious activity on my account. I never had a Diners card in the first place.

spam

Caller: citibank acting for Virgin Money

This is legitimate. Hard to hear them. Philipino and Indian call centres acting for Citibank. Most likely a credit card in another name like Coles or Virgin Money. Citibank manage a lot of those cards.

Caller: Citibank

This one's legit - it was in regards to an application for a credit card (although their operation is kinda a bit disorganised and the staff are a bit hit and miss with their knowledge and service, so it had me wondering a few times)