8 Ways to Earn Miles Without an Airline Credit Card

Airline credit cards are a great way to earn miles with your favorite frequent flyer program. But you don't need a co-branded or premium card to rack up rewards. While they may take longer, these options can help you earn the miles you need to book a free flight or take advantage of other redemption offers:

-- Book flights using your frequent flyer number.

-- Use online shopping portals.

-- Participate in dining programs.

-- Get a new bank account.

-- Book hotel stays.

-- Book with partners.

-- Share your opinion.

-- Buy them.

Tip One: Book Flights Using Your Frequent Flyer Number

You can get miles if you provide your frequent flyer number when you book your trip and pay out of pocket. Each airline has a different rate for which you'll earn miles, and how much you earn can depend on your status with the airline, the type of fare, the ticketing airline and the operating airline.

[Read: Best Airline Credit Cards.]

"Having airline elite status allows you to earn bonus miles on the flights you take," says Angelina Aucello, author of Angelina Travels, a rewards travel blog. "And if you have airline status with one airline, you can leverage that to find status match opportunities for other airlines, too."

If you forget to add your number or haven't yet signed up for the airline's loyalty program, call the airline or visit its website to request credit.

Tip Two: Use Online Shopping Portals

Many airlines allow you to earn miles when you shop through their online portals. How much you can earn typically depends on the retailer and how much you spend. Here are some shopping portals from major airlines:

-- American Airlines AAdvantage eShopping

-- British Airways Avios eStore

-- Hawaiian Airlines HawaiianMiles Online Mall

-- Alaska Airlines Mileage Plan Shopping

-- United Airlines MileagePlus Shopping

-- Southwest Airlines Rapid Rewards Shopping

-- JetBlue Airways ShopTrue

-- Delta Air Lines SkyMiles Shopping

Shopping online can be a great way to earn miles fast, but overspending can neutralize any value you receive from the rewards you earn.

As such, it's important to use shopping portals only if you're already planning to spend the money. Also, don't make your decision on where to buy an item or service based solely on the rewards rate. Shop around to make sure you're getting the best price.

If you're looking to maximize how many miles you earn regardless of which airline it is, Aucello recommends using sites like CashbackMonitor.com to compare rates for different retailers.

You might even be able to earn miles when you're shopping offline, Aucello adds. "If you're out and about, the United MileagePlus X app is an awesome way to earn a bunch on everyday spending, too." Just pick a participating merchant and enter a dollar amount, and you'll receive a gift card you can use for in-store purchases. You'll receive miles for the purchase as soon as you buy the gift card or after you redeem it.

Tip Three: Participate in Dining Programs

The average U.S. household spent more than $3,000 in 2017 on food away from home, according to the federal Bureau of Labor Statistics. Depending on where you dine out, you could earn miles for every dollar you spend.

Most of these programs are offered through a company called Rewards Network. Here's what you can earn:

-- American Airlines AAdvantage Dining: up to 5 miles per dollar spent

-- Spirit Airlines Free Spirit Dining: up to 5 miles per dollar spent

-- Alaska Airlines Mileage Plan Dining: up to 5 miles per dollar spent

-- United Airlines MileagePlus Dining: up to 5 miles per dollar spent

-- Southwest Airlines Rapid Rewards Dining: up to three points per dollar spent

-- Delta Air Lines SkyMiles Dining: up to 5 miles per dollar spent

-- JetBlue Airways TrueBlue Dining: three points per dollar spent

If you earn 5 miles per dollar on $3,000 each year, you'd earn 15,000 miles over the course of a year. Depending on the airline, that could be worth at least enough to cover one or two one-way tickets.

"I register every credit card I have to ensure I'm not missing out on any rewards," says Lee Huffman, a travel blogger at BaldThoughts.com. "When traveling to a new city, I research which restaurants are participating so that I can try new food and earn extra miles."

To get credit for your restaurant purchases, sign up for your preferred program, and register your credit or debit cards that you might use when eating out.

Tip Four: Get a New Bank Account

If you're loyal to American Airlines, a couple of banks offer the opportunity to earn more rewards.

Online bank UFB Direct, for instance, offers 1 mile for every $3 in point-of-sale transactions with your debit card. You can earn up to 120,000 miles each year. BankDirect, another online bank, offers opportunities to earn miles with its Mileage checking, money market and certificate of deposit accounts.

Tip Five: Book Hotel Stays

If you're taking a road trip, you won't get the chance to earn miles from a flight. But you can if you book hotel stays along the way.

Websites like PointsHound and Rocketmiles allow you to earn miles with frequent flyer programs for every hotel stay you book through their site. But again, shop around to make sure you get the best rate.

[Read: Best No-Annual-Fee Credit Cards.]

Tip Six: Book with Partners

Some airlines have partnerships with other travel brands, enabling you to earn miles throughout your vacation. Southwest Airlines, for instance, offers points when you book hotels, car rentals, shuttles and various travel experiences, like tours and museum tickets.

Check your favorite airline's website to find out if it partners with other travel brands for rewards earning. Keep in mind, though, that by booking through the airline, you may miss out on the chance to earn rewards with the partner brand. Also, some car rental companies apply a surcharge on reservations that earn frequent flyer miles.

Tip Seven: Share Your Opinion

A handful of airlines offer miles when you complete surveys:

-- Alaska Airlines: The Opinion Terminal

-- American Airlines: e-Rewards

-- JetBlue Airways Points for Surveys

-- Southwest Airlines e-Rewards

-- United Airlines Opinion Miles Club

Keep in mind, though, that while completing surveys is easy, you may not earn much for your effort.

"Time is money, and I personally find that taking surveys to earn miles is often time-consuming," says Aucello. "I'd only recommend doing so as a free and easy way to extend the life of your miles if you think they might be expiring."

Tip Eight: Buy Them

Buying airline miles may be one of the easiest ways to get what you want, but it's also one of the most expensive. With United Airlines, for instance, you'll pay $35 per 1,000 miles with a minimum purchase of 2,000 miles. That's a cost of 3.5 cents per mile, which is far more than the value you'll get when you redeem them.

As a result, it's rarely a good idea to buy miles, unless you need a few more to book a trip or your rewards are expiring and buying some can push off the expiration date.

"The only time I recommend travelers buy miles is if you need a few additional miles to book an award ticket," says Huffman. He also recommends paying attention to seasonal promotions, where miles may come with a lower price tag.

[Read: Best Balance Transfer Credit Cards.]

The Best Way to Earn Miles

There are several ways to earn miles without ever using a co-branded airline or premium rewards credit card, but some can be costly or time-consuming. You'll earn miles much more quickly if you have a card that offers a sign-up bonus and ongoing rewards.

"Credit card sign-up bonuses are the simplest way to earn large quantities of airline miles quickly," says Huffman. "Once you have the credit card, putting all of your expenses on the card adds up quickly toward free flights."

If you have an airline credit card, you can still use these other strategies to earn miles. It's a good idea to focus on the options that require less effort. For example, you can register your airline credit card with your favorite airline's dining program, multiplying your earning power every time you eat out -- without a lot of legwork.

Whatever you do, consider all your options, choosing the one that works best for your needs and is feasible for your spending habits. Once you start, you can watch your rewards balance grow.