I held off on opening the Business Platinum card until I discovered Amex Centurion Lounges. This benefit alone is worth the $595 annual fee for me

• I had received offers for the Business Platinum® Card from American Express, but was never tempted to apply until I discovered the Amex Centurion Lounge at San Francisco Airport (SFO).
• Amex Centurion Lounges offer a comfortable place to relax before a flight, with complimentary gourmet food and drinks.
• Only holders of the Business Platinum Amex, the Platinum Card® from American Express, or the Centurion cards can access these lounges.
• I applied for the Business Platinum to get lounge access, and haven't regretted it a bit.
• Now is a great time to apply for the Business Platinum, as you can earn up to 100,000 points as a welcome bonus: 50,000 points after you spend $10,000 and an extra 50,000 points after you spend an additional $15,000 all in the first three months.

Recently, before a five-hour flight from San Francisco International Airport to JFK, my family ran into a bit of bad luck: Our flight was delayed. It wasn't just delayed a few minutes; it was delayed by about three hours. After a night of tossing and turning before heading to the airport, we were in no mood to sit there at the gate for eons, or to eat at one of the overpriced fast-food stalls.

Out of the corner of our eyes, we spotted the American Express Centurion Lounge. That was just what we needed - a place to rest and relax, with food and drinks.

How to access Amex Centurion Lounges

Since I have an American Express Platinum card, I figured we could just waltz right in. Sadly, the card in my possession was American Express's Optima Platinum card - not the right Amex Platinum to get entry.

I learned the hard way that Centurion Lounges are exclusively available for holders of the regular Platinum Card from American Express, the Business Platinum Card from American Express, and the Centurion (black) cards, which are invite-only.

Why I finally applied for the Amex Business Platinum

Beyond the front counter, I could spy couples laughing, I could smell the aroma of freshly brewed coffee, and I was envious of the plate of fresh food a man walked by with. We left crestfallen. We returned to our crowded gate and squeezed into whatever seats we could find while picking on overpriced premade sandwiches and drinking water that cost $4.50 a bottle. I decided right then and there: I needed to upgrade my credit card situation.

I'd been receiving Amex Business Platinum offers in the mail for the business I inherited from my father (it's a vinyl record store called Grooves, so if you're ever in San Francisco, stop on by!). I would routinely tear the offers into little pieces and toss them away, but after seeing the Centurion Lounge at SFO, I was ready to take the plunge. While all the card's perks were tempting, the lounge access really was what sealed the deal.

The Business Platinum card allows me, as well as two guests, to hang out in the Centurion Lounge free of charge as long as our flight is departing that same day. You're only allowed access to the Centurion Lounge three hours before your flight, so you won't be able to go there eons earlier and camp out. You card allows two guests to accompany you; if you have more than two, you can purchase a day pass for them at $50 per person.

Read more: Amex's Business Platinum is one of the best cards for small business owners

Business Platinum card details

In addition to the Centurion Lounge, the card allows entry into the International American Express Lounges, Escape Lounge US, Delta Sky Club (when you're flying Delta), Airspace, Lufthansa Lounges, and a variety of lounges via Priority Pass.The Business Platinum Amex costs $595 a year. My family of three flies quite a bit throughout the year, and we usually about $50 on food and beverages before each leg of our trip. By going to the lounge instead, the card would pay for itself after six trips.

The card is currently offering an elevated welcome bonus, so if you're interested, it's a great time to apply. Instead of the usual 75,000-point bonus, you can earn up to 100,000 Amex points: 50,000 after you spend $10,000 and an extra 50,000 after you spend an additional $15,000 all on qualifying purchases in the first three months. This offer is available until December 4.

That's a high minimum spending requirement, but this is a business card, and for some businesses it could be easy to earn.

Click here to learn more about the Business Platinum card from American Express from our partner The Points Guy.

The Centurion Lounge at SFO

At SFO, the Centurion lounge is in Terminal 3, which is the hub for United flights. Unfortunately, if you happen to be flying out of Terminal 1 or 2, you'll have to go through security twice, since the terminals aren't connected. So, if you do make the trek to the lounge, make sure to keep an eye on the clock and allow enough time to get to your gate. The lounge does have a screen with the estimated times of departure, so you can easily keep track if your flight changes.

There are spaces for kicking back and relaxing, tables to hang with fellow travelers, and desks with outlets if you need to get work done. The space is accented with rustic suitcases and vintage photographs of counterculture icons of the 60s like Jimi Hendrix and Sly Stone.

Besides being a comfortable place to wait, one of the main draws is the food. You can see the chefs behind the buffet whipping up fresh (and healthy) fare. The menu changes frequently. When I was there, they had bountiful platters of asparagus and chicory salad, a vegetarian curry, perfectly cooked chicken breasts, and a delicious gemelli pasta with broccolini, fennel, peas, and lemon among many other options. There were also bowls of fresh fruit for the taking.

The other popular place in the lounge is the bar, a destination for many to ease those preflight jitters. Along with a wide array of domestic, imported, and craft beers, they host a full roster of top-shelf liquors such as Maker's Mark Bourbon, and Don Julio Tequila. If you ate too much of the food, there's also Fernet to ease your tummy. For those who like vino, there's a self-serve area with wine dispensers featuring California wines from vintners such as Buehler, Justin Hope, Oberon, and Dutton Goldfield. All of these drink selections are free of charge with a card that gets you access to a Centurion lounge. It's like being at a fantastic hosted party.

There are TV screens in various spots and, most importantly, high-speed Wi-Fi. There's also bathrooms stocked with L'Occitane products and a shower suite if you need to really clean up. If you have little ones with you, there's a large family room with cartoons on the big screen and a few communal toys.

Other Centurion Lounge locations

Currently, the American Express Centurion Lounge has locations Dallas, Miami, Seattle, Philadelphia, LGA - New York, Hong Kong, Houston, Las Vegas, and San Francisco with locations coming soon to Denver, New York's JFK, Los Angeles, London Heathrow, Charlotte, and Phoenix.

Access to the lounges is just one of the many perks that come with the Business Platinum Amex card, and so far, the one we've appreciated the most. Now, we actually look forward to hanging out at the airport!

Click here to learn more about the Business Platinum card from American Express from our partner The Points Guy.

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