The best credit card bonuses this week can get you $1,200 in airfare, $750 in cash back, or big bonuses on grocery spending — but some offers end soon

• December 31 is just a few days away, so be sure you've made the most of credit card benefits that reset every calendar year, such as statement credits toward Uber, Saks, and airline incidental fee purchases on The Platinum Card® from American Express.
• The record-high offers on the three Southwest personal cards now have an end date — apply by February 8, 2021, and remember these bonuses qualify toward earning the Southwest Companion Pass.
• Several elevated card offers are only available for a couple more weeks — including the 5x grocery bonus that comes with the welcome offer on the Chase Freedom Flex℠ and Chase Freedom Unlimited®, which ends January 13, 2021.
• The increased bonuses on the United℠ Explorer Card, Marriott Bonvoy Brilliant™ American Express® Card, and Marriott Bonvoy Business™ American Express® Card will also end on the same date.
• Read Business Insider's guide to the best rewards credit cards for more top picks.

As we say goodbye to 2020, many of us are planning a fresh start for the new year — including stocking up on credit card rewards for trips once the pandemic ends.

If you're considering adding a new card or two in 2021, picking the best credit card might not only depend on the types of rewards you like to earn and your spending habits. Several increased credit card welcome bonus offers will end in just a couple of weeks, including on the United℠ Explorer Card, Chase Freedom Flex℠, and Marriott Bonvoy Brilliant™ American Express® Card.

There's also now an end date for the elevated offers on the Southwest personal cards— apply by February 8, 2021, to earn a record-high bonus with the Southwest Rapid Rewards® Plus Credit Card, Southwest Rapid Rewards® Premier Credit Card, and Southwest Rapid Rewards® Priority Credit Card.

Other whopper bonuses, such as the sky-high offers on the Chase Ink Business cards, don't have a specified end date yet — but we know they won't be around forever.

Beyond these big offers, it's your last chance to take advantage of credit card benefits that will reset at the end of the year. By December 31, make sure you've used up shopping and travel credits with these cards:

• The Platinum Card® from American Express— Up to $200 in airline incidental fee credits per calendar year on your selected airline, up to $35 in Uber credits (works for Uber Eats, too) in December, up to $50 in Saks credits from July to December
• The Business Platinum Card® from American Express— Up to $200 in airline incidental fee credits per calendar year on your selected airline, up to $100 in Dell credits from July to December 
• Hilton Honors American Express Aspire Card— Up to $250 in airline incidental fee credits per calendar year on your selected airline
• Citi Prestige® Card— Up to $250 in travel credits per calendar year 

If you're stuck for ways to use up your Amex airline credit, you might consider pre-paying for checked bags or seat selection on an already-booked trip, or gifting lounge passes to a friend or family member who is traveling soon.

Best increased credit card bonuses ending soon

Mark your calendar for January 13, 2021, because these limited-time card offers end on that date:

• Chase Freedom Flex℠ (5x grocery bonus only)
• Chase Freedom Unlimited® (5x grocery bonus only)
• United℠ Explorer Card
• Marriott Bonvoy Brilliant™ American Express® Card
• Marriott Bonvoy Business™ American Express® Card

And there's now an end date for the elevated welcome bonuses on the Chase Southwest personal cards— apply by February 8, 2021, to take advantage of these record-high offers:

• Southwest Rapid Rewards® Plus Credit Card
• Southwest Rapid Rewards® Premier Credit Card
• Southwest Rapid Rewards® Priority Credit Card

Read more details on these offers below:

Chase Freedom Flex and Unlimited: Earn 5x on up to $12,000 in grocery spending

There's now an end date for the 5x grocery welcome bonus on the Chase Freedom Flex℠ and Chase Freedom Unlimited® cards, and it's coming up fast.

Both cards currently offer $200 after spending $500 in the first three months from account opening, plus 5% cash back (5x Chase Ultimate Rewards points) on up to $12,000 in spending at grocery stores in the first year. The $200 bonus is sticking around, but you'll only receive the 5x grocery bonus if you apply by January 13, 2021.

The 5% bonus is one of the best deals around for grocery spending, and, if you spend the full $12,000 at grocery stores the first year, works out to an extra $600 cash back or 60,000 Chase Ultimate Rewards points. 

United Explorer Card: Earn up to 70,000 MileagePlus miles

The increased offer on the United℠ Explorer Card will also end on January 13, 2021. The card currently offers up to 70,000 United miles: 60,000 bonus miles after you spend $3,000 on purchases in the first 3 months your account is open (plus, an additional 10k bonus miles after you spend $6,000 in the first 6 months).

United miles don't expire, so there's no harm in building a stash of miles now to use for flights on United or its partners later. Keep in mind that United is a Chase Ultimate Rewards transfer partner, so if you value flexibility you might be better off with cards like the Chase Sapphire Preferred® Card, Chase Sapphire Reserve®, or Ink Business Preferred® Credit Card.

American Express Marriott cards: Earn up to 125,000 Marriott Bonvoy points

Both Amex-issued Marriott Bonvoy credit cards have limited-time increased bonuses that will also end on January 13, 2021. 

The Marriott Bonvoy Brilliant™ American Express® Card's elevated bonus is double the usual offer: Earn up to 125,000 Marriott Bonvoy points. Earn 100,000 bonus points after you spend $5,000 in purchases on your new Card in your first 3 months. Plus, earn an additional 25,000 bonus points after your first anniversary of Card Membership. Offer Expires 1/13/2021. 

And for small-business owners, the Marriott Bonvoy Business™ American Express® Card also has a Limited Time Offer: Earn 100,000 Marriott Bonvoy points after you use your new Card to make $5,000 in purchases within your first 3 months of Card Membership. Earn up to $150 in statement credits within your first 6 months of Card Membership for all eligible purchases on your Card on U.S. Advertising in select Media. Plus receive complimentary Marriott Bonvoy Platinum Elite status for one year (February 1, 2021-January 31, 2022). Offer ends 1/13/21.

Either of these cards would be a good pick if you like staying with Marriott brands and can use the automatic elite status each card provides. However, if you're not up to traveling just yet, be aware that Marriott points do expire after  24 months have passed without qualifying activity in your account — but due to COVID, the chain has paused points expiration until August 1, 2021.

Chase Southwest personal cards: Earn up to 80,000 Rapid Rewards points

Chase has now assigned an end date of February 8, 2021, for the huge offers on the Southwest Rapid Rewards personal cards, which are all offering up to 80,000 points (50,000 points after you spend $2,000 on purchases in the first 3 months ,and an additional 30,000 points after you spend $10,000 on purchases in the first 9 months). Because Southwest points are, on average, worth 1.5 cents each toward airfare, the bonus is worth about $1,200 in flights.

These are the highest bonuses ever offered on the Southwest Rapid Rewards® Plus Credit Card, Southwest Rapid Rewards® Premier Credit Card, and the Southwest Rapid Rewards® Priority Credit Card. Because Southwest points don't expire, this is a terrific opportunity to stock up on Rapid Rewards points — and save them for when you're ready to travel again. 

The timing of these elevated Southwest card bonuses is perfect if you have your eye on earning the Southwest Companion Pass in 2021. Between the bonus and points from meeting the minimum spending requirement, you'll be just 35,000 points shy of the 125,000 points required in a calendar year to qualify for the Companion Pass. 

Best ongoing increased credit card bonuses

These cards have improved welcome offers for a limited time, but we don't yet know when they'll end:

• The Platinum Card® from American Express
• Ink Business Unlimited℠ Credit Card
• Ink Business Cash℠ Credit Card
• American Express® Gold Card

Read more details on these offers below:

Amex Platinum card: Earn 75,000 Membership Rewards points

The elevated welcome offer on The Platinum Card® from American Express is still active, but it won't be around forever.  In addition to the welcome bonus of 60,000 points after your spend at least $5,000 in your first 3 months of account opening, new cardholders can earn 10x points per dollar spent at US gas stations and US supermarkets, on up to $15,000 in combined spending (then 1x) in the first six months of account opening.

Even if you're not traveling right now, the Amex Platinum 75k bonus is worth considering: Between up to $200 in Uber credits (including Uber Eats) and up to $100 in Saks credits each calendar year, plus the ability to use Membership Rewards points for a wide variety of redemptions (including many that don't involve travel), it's easy to get a ton of value from Platinum Card. 

Chase Ink Business Unlimited and Ink Business Cash: Earn $750 cash back

The Ink Business Unlimited℠ Credit Card and Ink Business Cash℠ Credit Card increased welcome offers to earn $750 bonus cash back after you spend $7,500 on purchases in the first 3 months from account opening are still active this week.

Small-business owners who want to earn lots of rewards in the new year can benefit from these all-time-high offers. Keep in mind the Chase Ultimate Rewards points you'll earn from these cards aren't just good for cash back — you've got options to redeem for travel, and even more flexibility (like transferring to Chase airline and hotel partners) if you also have the Chase Sapphire Preferred® Card, Chase Sapphire Reserve®, or Ink Business Preferred® Credit Card in your wallet.

American Express Gold Card: Earn 60,000 Membership Rewards points

The increased welcome offer on the American Express® Gold Card has stuck around for a while, and it's still worth a  look, especially since one of its key benefits is about to reset at the end of the year.

Along with 60,000 points after you spend at least $4,000 in your first 6 months of account opening, the American Express® Gold Card earns 4x Membership Rewards points on up to $25,000 spent at US supermarkets each calendar year (then 1x). This perk alone puts the card high on our list of top credit cards for buying groceries.

It's also a good credit card for dining because it earns 4x points at restaurants worldwide (including takeout and delivery) with no cap. 

Jasmin Baron is an associate editor at Personal Finance Insider, where she helps readers maximize rewards and find the best credit cards to fit their lifestyles. 

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