Seahawks vs. 49ers Best NFL Prop Bets for NFL Week 18 (Bet on Christian McCaffrey)

Breaking down the best prop bets for the Seattle Seahawks-San Francisco 49ers matchup in Week 18.

San Francisco 49ers running back Christian McCaffrey is a great prop target in Week 18. / Trevor Ruszkowski-Imagn Images

A divisional battle with the No. 1 seed in the NFC on the line takes place in Week 18, as the Seattle Seahawks hit the road to play the San Francisco 49ers on Saturday night.

San Francisco is looking to sweep the season series between these teams to earn the top spot in the conference, but both of these squads have been red hot, each winning six games in a row.

So, if you don’t want to bet on a side with this spread set at just 1.5 points, then the prop market is another way to get involved in this game! 

I’m eyeing a few plays for this NFC West battle, including a player prop for 49ers running back Christian McCaffrey. 

The 49ers have been humming on offense since Brock Purdy returned from a toe injury, but can they put up big numbers against the No. 2 defense in EPA/Play? 

On the Seattle side, Sam Darnold is looking to show he can win a big game after losing the No. 1 seed in the NFC last season when he was with Minnesota. 

Here’s a breakdown of each of my favorite prop bets for these two Super Bowl contenders in this Week 18 showdown. 

Best NFL Prop Bets for Seahawks vs. 49ers

Odds via DraftKings Sportsbook.

• Christian McCaffrey OVER 67.5 Rushing Yards (-111)
• Kenneth Walker III OVER 11.5 Rush Attempts (-113)
• Brock Purdy 2+ Touchdown Passes (-149)

Christian McCaffrey OVER 67.5 Rushing Yards (-111)

This is a tough matchup for Christian McCaffrey and the 49ers’ running game, as the Seahawks rank No. 1 in the NFL in yards per carry allowed (3.7) and No. 1 in EPA/Rush this season. Still, I’m buying the star back on Saturday night.

In Week 1, CMC turned 22 carries against Seattle into 69 yards. Not an efficient game, but he did clear this prop. The star back has seen a huge workload in recent weeks, carrying the ball at least 20 times in five games in a row.

With Brock Purdy under center this season, CMC has rushed for 69, 49, 81, 89, 53, 73, 117 and 140 yards. He’s cleared the 100-yard mark in back-to-back weeks, and he should receive a ton of touches in Week 18. 

At this number, McCaffrey is worth a look, even against an elite defense. 

Kenneth Walker III OVER 11.5 Rush Attempts (-113)

Seahawks running back Kenneth Walker III has cleared 11.5 carries in eight of his 16 games this season, and he’s coming off a 15-carry game against the Carolina Panthers in Week 17.

I wouldn't be shocked if the Seahawks lean on their run game in this matchup, as the 49ers are allowing 4.3 yards per carry and rank 21st in the NFL in EPA/Rush this season.

Walker is going to split time with Zach Charbonnet, but he’s handled at least 10 carries in 15 of his 16 games this season. So, there is a solid floor for the Seattle running back on Saturday night. 

I’ll take the OVER on Walker’s attempts, as he’s put together back-to-back productive weeks. 

Brock Purdy 2+ Touchdown Passes (-149)

Seattle has one of the best defenses in the NFL, but it allowed a pair of touchdown passes to Purdy in Week 1, and the star quarterback has been a touchdown machine in 2025.

In eight games this season, Purdy has multiple touchdown passes in six of them, including each of his last three games. In that three-game stretch, Purdy has thrown 11 touchdowns, and he even ran for a pair in Week 17 against the Chicago Bears.

The 49ers quarterback has 20 passing scores overall, and he did throw for 277 yards and two scores in Week 1 against this Seattle defense. I think he’s worth a look in this market given how often San Francisco has let him attack through the air since returning from a turf toe injury

Purdy has at least 30 pass attempts in four of his last five games and six of his eight games overall this season.

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Odds refresh periodically and are subject to change.

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