While it doesn’t influence our opinions of products, we may receive compensation from partners whose offers appear here. We’re on your side, always. See our full advertiser disclosure. Image source: Getty Images Today's mortgage rates are mixed, with some up, some down from yesterday. Here's what they look like: Mortgage Type Today's Interest Rate 30-year fixed mortgage 3.206% 20-year fixed mortgage 2.899% 15-year fixed mortgage 2.480% 5/1 ARM 2.943% Data source: The Ascent's national mortgage interest rate tracking.30-year mortgage ratesThe average 30-year mortgage rate today is 3.206%, up 0.004% from yesterday. At today's rate, you'll pay principal and interest of $432.69 for every $100,000 you borrow. That doesn't include added expenses like property taxes and homeowners insurance premiums.20-year mortgage ratesThe average 20-year mortgage rate today is 2.899%, up 0.019% from yesterday. At today's rate, you'll pay principal and interest of $549.80 for every $100,000 you borrow. Though your monthly payment will go up by $117.11 with a 20-year, $100,000 loan versus a 30-year loan of the same amount, you'll save $23,812.52 in interest over the course of your repayment period for every $100,000 you borrow.15-year mortgage ratesThe average 15-year mortgage rate today is 2.480%, down 0.004% from yesterday. At today's rate, you'll pay principal and interest of $666.04 for every $100,000 you borrow. Compared to the 30-year loan, your monthly payment will be $233.35 higher per $100,000 in mortgage principal. Your interest savings, however, will amount to $35,879.47 over the life of your repayment period per $100,000 of mortgage debt.5/1 ARMsThe average 5/1 ARM rate is 2.943%, down 0.038% from yesterday. With a 5/1 ARM, you lock in your initial interest rate for five years, but from there, your rate can increase year after year. However, it can also go down -- it'll depend on market conditions. Right now, you can get a much lower interest rate with a 5/1 ARM than with a 30-year fixed loan, so if you're not planning to stay in your home for more than five years, a 5/1 ARM could make sense. And even if you do decide to stay put longer, there's always the option to refinance to a new mortgage if your 5/1 ARM rate keeps climbing.Should I lock in my mortgage rate now?A mortgage rate lock guarantees you a specific interest rate for a certain period of time -- usually 30 days, but you may be able to secure your rate for up to 60 days. You'll generally pay a fee to lock in your mortgage rate, but that way, you're protected if rates climb between now and when you close on your home loan.If you plan to close on your home within the next 30 days, then it pays to lock in your mortgage rate based on today's rates -- especially since they're still pretty low. But if your closing is more than 30 days away, you may want to choose a floating rate lock instead for what will usually be a higher fee, but one that could save you money in the long run. A floating rate lock lets you secure a lower rate on your loan if rates fall before you close on your mortgage, and while today's rates are still pretty low, we don't know if rates will go up or down over the next few months. As such, it pays to:LOCK if closing in 7 daysLOCK if closing in 15 daysLOCK if closing in 30 daysFLOAT if closing in 45 daysFLOAT if closing in 60 daysThough mortgage rates have risen substantially over the past month, you should know that they're still fairly competitive on a historical basis. As such, now's still a good time to apply. This especially holds true if you have a strong credit score and low debt-to-income ratio, because those factors will make it more likely that you qualify for the lowest rates available. That said, if you're going to get a mortgage, don't just accept the first offer you're presented with. Rather, shop around with different lenders so you can compare your options and find the home loan that's best for you.A historic opportunity to potentially save thousands on your mortgageChances are, interest rates won't stay put at multi-decade lows for much longer. That's why taking action today is crucial, whether you're wanting to refinance and cut your mortgage payment or you're ready to pull the trigger on a new home purchase. Our expert recommends this company to find a low rate - and in fact he used them himself to refi (twice!). Click here to learn more and see your rate. While it doesn't influence our opinions of products, we do receive compensation from partners whose offers appear here. We're on your side, always. See our full advertiser disclosure here.We’re firm believers in the Golden Rule, which is why editorial opinions are ours alone and have not been previously reviewed, approved, or endorsed by included advertisers. The Ascent does not cover all offers on the market. Editorial content from The Ascent is separate from The Motley Fool editorial content and is created by a different analyst team.The Motley Fool recommends Bitcoin. The Motley Fool has a disclosure policy.Source