Mega Millions Is at $413 Million. So Why Did the Jackpot Only Grow $10 Million?

Figures are the official Mega Millions estimates checked the morning of Oct. 20, 2026. Estimates can change on drawing day as sales and rates move. Jackpot Dreaming is a personal project and is not affiliated with Mega Millions, Powerball or any lottery.

A smaller jump that isn't really smaller

Friday's drawing (Oct. 16) didn't produce a jackpot winner. The numbers were 2, 15, 31, 41 and 68, with Mega Ball 11, and the jackpot rolled from $403 million to an estimated $413 million for tonight.

If you've been following this run, $10 million looks like the jackpot is running out of steam. The four drawings before it added $24 million, $19 million, $21 million and $18 million. A $10 million bump feels like sales fell off a cliff.

They probably didn't. Look at the cash column instead:

Source: megamillions.com drawing data. Percentages are our arithmetic.

The cash pot went up $7.5 million, then $7.3 million, then $8.2 million. That last step is the second biggest cash gain of this entire run, behind only the $8.5 million added between the Oct. 2 and Oct. 6 drawings. So the real money grew faster, while the headline grew slower. That's not a typo. It's how the annuity math works.

How a Mega Millions jackpot actually grows

Three things are going on, and only one of them is ticket sales.

1. Sales feed the cash pool

Half of Mega Millions sales go back to players as prizes, according to the Mega Millions FAQ. Part of that prize money builds the jackpot pool. The cash option is defined as "all the cash in the Mega Millions jackpot prize pool," based on actual sales. That's the honest measure of how big the pot is.

When nobody hits, the pool carries forward and new sales stack on top. In this run the cash value started at $21.5 million after the jackpot reset to $50 million on July 31. Tonight it's $170.3 million. That's $148.8 million of growth over 23 rollovers, or about $6.5 million per drawing on average.

2. The numbers you see are forecasts

Here's a detail most people never hear. The participating lotteries meet every Tuesday and Friday morning to estimate the next two jackpots, adding up each state's own sales forecast, per the FAQ.

Mega Millions says as much as 70% of sales happen on drawing day itself, so nobody knows the final number in advance. The last jackpot shows how close they tend to get. The July 28 prize was advertised at $800 million ($344.2 million cash), and the final figure came in at $803 million ($345.5 million cash), based on actual sales, according to Mega Millions. That ticket was sold at a Wawa in Bradenton, Florida.

3. Interest rates turn cash into the headline

The advertised jackpot is the annuity: one payment now and 29 more yearly payments, each 5% bigger than the last. Mega Millions says the annuity value is based on the cash in the pool and that day's 30-year U.S. Treasury rate, which can change daily.

The logic is pretty simple once you see it. Higher rates mean a pile of cash invested today can fund a bigger stream of payments over 30 years, so the advertised number goes up. Lower rates shrink it. Same cash, different headline.

That's what seems to have happened since last week. Treasury's daily data shows the 30-year yield closed at 5.56% on Oct. 13 and 5.43% on Oct. 15 and 16. Lower rates, smaller annuity per dollar of cash, so the ratio climbed from 40.2% to 41.2%.

Run the cash through Friday's ratio and you get roughly $423 million instead of $413 million. That $10 million gap is the rate effect, give or take.

A caveat we want to be upfront about: Mega Millions doesn't publish the exact rate snapshot or formula it uses for each estimate, and Treasury closing yields aren't the same thing as a mid-morning rate. The direction lines up with what the game says drives the annuity, but treat our explanation as the likely one, not a confirmed one.

It works the other way, too

This run has a mirror-image moment. Between the Sept. 22 and Sept. 25 drawings, the headline jumped $23 million ($277 million to $300 million), the biggest increase in the run up to that point. The cash pot? Up $6.8 million, exactly what it had added the drawing before, when the headline only rose $16 million.

What changed was rates. The 30-year Treasury yield closed at 5.29% on Sept. 22 and 5.47% by Sept. 24. Cash fell from 42.3% of the headline to 41.4%. At the old ratio, $124.1 million in cash would have been advertised around $293 million. So part of that splashy "$300 million" milestone was interest rates, not a sales surge.

Which is why comparing jackpots across months by the headline alone can mislead you. A $413 million jackpot when rates are high and one when rates are low aren't the same amount of money.

What the annuity would actually pay

Because the payments grow 5% a year, the first check is much smaller than "$413 million divided by 30." Using the same schedule logic as our calculator, the first payment on a $413 million annuity would be about $6.2 million before taxes, and the 30th about $25.6 million. The real schedule is set from the actual jackpot after the drawing, so these are estimates.

We covered what a winner keeps after taxes in last week's $403 million breakdown, and the cash vs. annuity tradeoff in our lump sum vs. annuity guide, so we won't redo it here. For tonight's after-tax numbers in your state, use the calculator.

Did the $5 ticket change how fast jackpots grow?

Mega Millions moved to a $5 ticket with a built-in multiplier in April 2025. The game says the price change allows a $50 million starting jackpot and "faster-growing jackpots" once momentum builds. Jackpot odds are 1 in 290,472,336.

In this run, the early climb was slow and steady: $50 million, then $60, $70, $80, $90 and $100 million in $10 million steps through Aug. 18. Bigger steps came later. Whether jackpots now grow faster overall is something one run can't answer. It would take a comparison across many runs with rates held constant, and there are less drawings under the new format than we'd like to work with. We're leaving that one open.

Tonight, and the rest of the week

• Mega Millions: Tuesday, Oct. 20, 11 p.m. ET. Estimated $413 million, cash $170.3 million. Tonight is the 24th drawing since the July 28 win.
• Powerball: Wednesday, Oct. 21, estimated $635 million, cash $267.5 million, per powerball.com. Cash is about 42.1% of that headline.

If you play, treat it as entertainment money. Our odds explainer walks through what a single ticket is really worth. And as these runs get longer, so do the scam attempts.

FAQ

Why did the Mega Millions jackpot only go up $10 million?

The cash pot actually grew a healthy $8.2 million. But the advertised annuity is converted from cash using the 30-year Treasury rate, and rates dipped late last week, so cash went from 40.2% of the headline to 41.2%. At Friday's ratio, tonight's cash would have been advertised around $423 million.

What is the cash value of tonight's $413 million Mega Millions jackpot?

An estimated $170.3 million, per megamillions.com on the morning of Oct. 20, 2026. The final amount depends on actual sales.

How does a Mega Millions jackpot grow?

Ticket sales build the cash jackpot pool, which rolls over when nobody wins. The lotteries forecast sales twice a week, then convert the projected cash into a 30-payment annuity using the 30-year Treasury rate. Both sales and rates move the headline.

Do interest rates change the Mega Millions jackpot?

They change the advertised annuity, not the cash. Higher rates mean the same cash funds a bigger 30-year payment stream, so the headline rises. Lower rates do the opposite.

When was the Mega Millions jackpot last won?

July 28, 2026, by a single ticket sold in Bradenton, Florida. The final jackpot was $803 million ($345.5 million cash). Tonight is the 24th drawing since then.

What time is the Mega Millions drawing tonight?

11 p.m. Eastern on Tuesday, Oct. 20, 2026. Sales cutoffs vary by state and are earlier, so check your state lottery.

Sources

• Mega Millions official drawing data: Oct. 20, 2026 estimated jackpot $413 million, cash $170.3 million; Oct. 16 jackpot $403 million (cash $162.1 million), no jackpot winner, numbers 2, 15, 31, 41, 68, Mega Ball 11; earlier drawing estimates and cash values in this run back to the July 31 reset at $50 million ($21.5 million cash).
• Mega Millions FAQs: 50% of sales to prizes; cash option equals the cash in the jackpot pool; annuity of 30 payments growing 5% a year based on the cash value and the 30-year Treasury rate; jackpots estimated at Tuesday and Friday morning meetings from state sales forecasts; up to 70% of sales on drawing day; $5 price from April 2025 with a $50 million starting jackpot; drawings at 11 p.m. ET.
• Mega Millions How to Play: $5 per play with built-in multiplier; jackpot odds 1 in 290,472,336.
• Mega Millions news release, July 29, 2026 and Jackpot History: July 28 Florida jackpot of $803 million ($345.5 million cash) vs. the $800 million ($344.2 million cash) estimate; reset to $50 million.
• Florida Lottery release via Mega Millions: winning ticket sold at Wawa, Bradenton.
• U.S. Department of the Treasury, Daily Treasury Par Yield Curve Rates: 30-year closing yields of 5.56% (Oct. 13), 5.43% (Oct. 15 and 16), 5.29% (Sept. 22) and 5.47% (Sept. 24), 2026.
• Powerball: Wednesday, Oct. 21, 2026 estimated jackpot $635 million, cash $267.5 million.
• Jackpot Dreaming calculator: annuity schedule logic (30 payments, 5% yearly growth) used for the estimated first ($6.2 million) and last ($25.6 million) pre-tax payments.