What in the world does the 10-year Treasury rate have to do with personal finance?

Turns out, it's quite a lot.

The 10-year Treasury rate graph from cnbc.com on September 3, 2026

I'm buying a new car tomorrow. This is a decision I've grappled with for a long time and I'll write more about it later. But it provides an interesting lens through which I was reading this morning's headlines. One of the things I love about personal finance is there is always something new to learn. Today, for me, that's about 10-year Treasury notes and their impact on my day-to-day life. Today, in the email newsletter "1% Better", this story caught my attention. I also find this story incredibly interesting because of the impact that timing has on our finances.

Timing of when you need to do something such as replace a car or use investment income is something we might try to plan for, but there are forces that are largely beyond our direct control that directly impact those plans. Learning about the 10-year rate is another great example of the impact of timing on all sorts of financial decisions. For long term context to today's article, the current 10-year rate is 4.81%. A year ago it was about 4.06%. The current rate is the highest it has been since 2023.

Here's the actual piece from 1% Better that caught my attention and sent me down this rabbit hole.

Screenshot of the article from 1% Better newsletter on September 3, 2026.

The renewed fighting with Iran will likely continue to push energy costs up. Diesel is up 51% since the fighting began, and fuel costs feed into almost everything else we buy, so that's seen as a further sign that inflation will continue to rise. And, with the national debt crossing $40 trillion in August, the Treasury has to keep issuing new debt while also refinancing what's maturing. When there's that much supply, prices fall and yields rise.

Here's the part I didn't expect. War usually pushes Treasury yields down, because scared money runs toward the safest thing it can find and US Treasuries are that thing. Yields went up anyway. So the inflation and debt pressures were strong enough to overwhelm all that safety buying.

Here's what I learned and how I see it playing out in my life.

The 10-year Treasury yield is impacted by the market rather than a contractual or legislative authority. It represents the daily buying and selling activity of about $900 billion in treasuries per day. So, the fluctuations and changes in that daily activity give a relatively accurate picture of what the people in the market are thinking in relation to inflation, growth, and Fed policy.

We all worry about "the Fed" (aka the Federal Reserve) and what they will do with interest rates, but they take action much less frequently than rates actually change. Currently, the Fed meets about 8 times a year. So, the Fed sets rates that then have some contractual ties to what banks and others can do. The most direct link is to credit card interest rates. The Fed also acts as a signal on the current and future state of the economy. However, the 10-year is based on actual day-to-day buying and selling so it gives us a continuous picture rather than this 8 times yearly look.

Interest rates on things like home, auto, and personal loans change far more often than the 8 times a year the Fed meets. And, they change based, at least in part, on what the 10-year Treasury yield is doing. Auto and personal loans have the weakest tie to the 10-year rate of the three, but it's an example that also allows me to put the timing aspect into an interesting perspective - along with the value of doing the hard work to improve your credit score.

I'm purchasing a new car tomorrow, and I'm going to finance a portion of the purchase. Thankfully, I'm "well qualified" and will get GM based financing and a lovely 1.9% interest rate - in which case that debt is a tool in my financial toolbox rather than a drag on my budget. However, if I was not "well qualified" (i.e. I didn't have a solid credit score) or I wasn't working with a car manufacturer that has decided to run a pricing promotion, the rate for car loans right now averages 6.94% for a new car. For a used car, loan rates average around 11.4% (both rates came from Bankrate).

I've been navigating this car buying decision for a while. When I first started looking, about a year ago, the quotes I was getting were in the high 5s.

I wanted to put that in perspective of where I started out my financial life. For an entry level new car (priced at $24,000) on a 60 month loan term with minimal down payment and no trade in value - so basically my life when I bought my first car, that equates to $4,786.09 in interest paid over the life of that loan - and loan payments of $507.77 a month. I constantly worry that we're creating a market where the next generation can't actually thrive. (For those that check my math, I ran the calculation including all the titling and fees in the loan price so the financed amount is around $25,680.)

My first car (a Dodge Neon, lovingly named Charlie) was around $11,000 and I secured it with a 0% loan (and that was with less than stellar new borrower credit). My payments were around $175 a month (due to a couple of incentive offers). While according to the calculators, that $11,000 in my 20s is roughly equivalent to the $24,000 now, the interest rates are the real concern here.

The 10-year Treasury rate also impacts mortgage rates as well as things like target-date funds (which for me could impact the 529 accounts I have set up for my great nieces and nephews), annuity payouts and pensions (which I have among my retirement portfolio), and federal student loans (which impact the higher education industry I work closely with all the time).

Let's look at those in reverse.

Federal student loan interest rates get set each year based on the high yield of the last 10-year auction held before June 1, plus a fixed add on. The add on varies between undergrad, grad, and PLUS loans, at 2.05%, 3.60%, and 4.60% respectively, and there are caps on all three. So, a higher 10-year rate means higher student loan interest rates. But here's where timing shows up again. This year's rates got locked in at the May 12 auction, which came in at 4.468% and set undergraduate Stafford loans at 6.52%. That all happened before this month's run up. So what's going on right now doesn't touch the students heading to campus this fall at all. It hits the ones borrowing for 2027-28.

So, what about those annuities in my retirement savings? At the moment, the annuity in my retirement portfolio should benefit from the higher rate, because it's fixed rather than variable. Or, at least that's what I think it is after digging into this today. It's one more thing on my list to understand better about this account. Variable annuities work differently. The ones holding bonds lose value when the 10-year rises. The ones holding equities follow the stock market.

Here's the part that surprised me. If rates are still elevated in roughly thirteen years when I annuitize, that probably works in my favor. Payout rates get set from prevailing rates at the time, so a higher 10-year means a bigger monthly check. The scenario I should actually worry about is annuitizing when rates are low. Again, we can save and save and save, but timing always plays a role.

And, finally, on those 529 plans, I need the kids to stop aging. (I mean, I'd like them to stay little forever, but they just refuse to do that). The oldest is in 8th grade so we don't need the funds for another four years. Right now, his account - and all the other kids' accounts - are largely stocks so the 10-year rate could be mildly helpful as it increases. However, if rates spike in the year or two right around withdrawal, we could see negative impacts.

Technical note - the 529 plans we're in are "age-based" but they behave much like "target-date" funds and give us another way to look at this timing issue specifically.

And, now, let's wrap this up by understanding how the 10-year rate is tied to mortgages. When my housemate and I bought our house in July 2023, we came from two paid off homes. Neither of us was excited about jumping back into a mortgage, but it was the right decision for us. However, we hoped that mortgage rates would decline so that we could refinance and pay off our mortgage even faster than we already are on track to do. According to Bankrate, average mortgage rates in July 2023 on a 30-year fixed mortgage were between 6.81% and 7.00%. We got a more advantageous rate at the time, but it's still high compared to the rates we purchased our previous homes at. Sadly, rates haven't moved much in the 3 years since we purchased. Freddie Mac has the 30-year average at 6.7% right now. Our hopes of refinancing are being eclipsed by our personal strategy to simply pay more on each payment to get it paid off as soon as possible.

So, what does the 10-year rate have to do with that mortgage interest rate?

A 30-year mortgage almost never actually lasts 30 years. People sell, or they refinance, so the average one gets paid off in about seven to ten years. That makes the 10-year Treasury the closest comparison an investor has, and that's why mortgage rates get priced off of it rather than off of whatever the Fed is doing. But lenders add onto that 10-year Treasury rate. They add a spread on top to cover the risk that you'll pay the loan off early, the risk that you won't pay it at all, the cost of servicing the loan, and whatever return investors are looking for on mortgage-backed securities that month.

And here's where this got really interesting to me. In July 2023, when we closed, the 10-year rate was 3.90%. Today it's 4.81%. So the 10-year has gone up almost a full percentage point in the three years we've owned this house. And mortgage rates went slightly down.

That happened because the spread changed. Back in 2023, lenders were charging close to three percentage points over the 10-year, which was unusually wide. Today it's down to about 1.9 points, which is much closer to the historical norm. So the 10-year climbed, the spread narrowed, and the two of them very nearly cancelled each other out.

Which means our rate hasn't actually been frozen for three years. Two really big things were happening in opposite directions and they just happened to land in about the same place. I find that oddly comforting and I'm still working out why.

It also explains why our strategy of just paying more each month feels like the right one. Whether the 10-year falls far enough to make refinancing worth the closing costs is entirely outside my control. Paying extra toward principal is entirely inside it. At a rate near 6.5%, every extra dollar I put toward principal earns me a guaranteed 6.5%, which beats the risk-free return I can get almost anywhere else.

I loved learning a little more about this national headline and how it could impact my - and your - daily lives. I'm also fascinated by how timing impacts our finances in ways that are within and outside of our control. Join the conversation here in the comments. What financial topics have caught your eye that you'd like to learn more about? How has timing played into your financial life?

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Does all of this make your head spin and you'd rather work with a financial coach to help you make a solid car buying decision? Book a no obligation call with me.

Want to run these numbers for yourself? As an "almost" (more on that later too!) Accredited Financial Counselor, I've tested out hundreds of calculators and my favorite for auto loans is the one at Calculator.net.

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