Is Capital One Quicksilver a Visa or Mastercard?

Yes, the Quicksilver Cash Rewards credit card is a Mastercard.

Capital One Quicksilver is a Visa card, not a Mastercard. If approved for Capital One Quicksilver, you’ll receive either a Visa Platinum or Visa Signature version of the card. Visa Platinum cards have credit limits starting at $5,000. Visa Signature cards have limits starting at $10,000. To be approved for the Capital One Quicksilver card, you’ll need at least good credit. Quicksilver has a $0 annual fee and earns unlimited 1.5% cash back on all purchases.

While the Capital One Quicksilver card is a Visa for new applicants, the Capital One QuicksilverOne card is a Mastercard. The QuicksilverOne card accepts applicants with limited credit history and gives the same 1.5% cash back rate as the Quicksilver card. However, unlike Quicksilver, QuicksilverOne has an annual fee: $39. It’s a great starter card though. It’s actually interesting to note that if you get the Quicksilver card as an upgrade from QuicksilverOne or Capital One Platinum (the other option for people with limited credit), you might receive a Quicksilver Mastercard. But that may or may not be the case for everybody.

Visa and Mastercard are both accepted worldwide, so you can rest assured that your Capital One Quicksilver card will work anywhere you need it to. You’ll get plenty of benefits from both too.

Capital One Quicksilver is a Visa, not a Mastercard. More specifically, Quicksilver can be either a Visa Platinum card or a Visa Signature card. 

You'll get Visa Signature if your credit limit is $5k or more. An excellent credit score most likely grant you access to the Visa Signature version, and it provides some additional benefits.

There must be two versions of the card then, that or they kept it MC when I requested a product change. Originally had QS One card and after about 1 year (maybe 1.5 years), I requested a product change to QS. My QS card is MC and not Visa. The QS One card is a Mastercard, so I am guessing Cap1 did not change it over to the Visa during product change. Only difference between the two is annual fee and MC vs Visa. Hasn't bothered me once that my QS is MC and not Visa. 

My Quicksilver is a Mastercard and my credit limit is $800

I had my Platinum MasterCard converted to a QuickSilver card as well and it remained a MasterCard. 

Hoping to eliminate some of the confusion here; per the Capital One web site, there are 3 separate and distinct versions of the Quicksilver credit card:

1. QuicksilverOne Rewards
   1. Credit requirement: Fair
   2. Annual fee: $39.00
   3. Card type: MasterCard
   4. Rewards: 1.5%
   5. Bonus cash: $0.00
   6. Intro APR: none
2. Quicksilver Rewards
   1. Credit requirement: Good
   2. Annual fee: $0.00
   3. Card type: MasterCard
   4. Rewards: 1.5%
   5. Bonus cash: $0.00
   6. Intro APR: none
3. Quicksilver Rewards
   1. Credit requirement: Excellent
   2. Annual fee: $0.00
   3. Card type: Visa
   4. Rewards: 1.5%
   5. Bonus cash: $200.00
   6. Intro APR: 0% for 15-months

The above said, I have the card outlined in item #2 above and per the agreement CapitalOne sent me, my card has “0.0% intro APR on purchases for 9 months; 26.99% variable APR after that”.  I’m not sure if their web site is just behind their current offering, or if they kind of have versions 2.a and 2.b of this particular card.