PlexusDx vs Willow

Both sell tirzepatide. PlexusDx costs $189 a month and Willow costs $399, a difference of $210 a month or about $2,520 a year. The desk reads it as follows.

PlexusDx is pharmacy transparency and genetic testing. Willow is straightforward single-price plans. They are not aimed at the same person, and the cheaper one is not automatically the right answer — though on this board it usually is.

Advert against bill. PlexusDx advertises $129 and bills $189; Willow advertises $399 and bills $399. The gaps are different sizes, which means comparing the two on their advertised prices gives you the wrong answer.

Side by side

Prices verified 2026-09-18. "True monthly cost" is what you are billed in month two, once any introductory rate has lapsed and any membership has renewed.

The split

3 differences on the record. The others match.

What each puts on the record: PlexusDx

• No membership or platform fee is charged alongside the medication.
• Publicly names six 503A pharmacy partners: Belmar, Strive, Epiq Scripts, Casa Pharma Rx, The Pharmacy Hub and Foothills.

Where it wins: The most detailed pharmacy disclosure in this comparison — six named 503A partners. Watch for: The advertised "from $129" is the programme floor. Budget $189/month for the compounded injection tier.

What each puts on the record: Willow

Where it wins: A single price with no membership arithmetic. Watch for: There is little published detail on how dose changes are handled. Ask before committing.

In each one’s favour

PlexusDx.

• The most detailed pharmacy disclosure in this comparison — six named 503A partners.
• Names its prescribing physicians along with their NPI numbers.

Willow.

• A single price with no membership arithmetic.

PlexusDx scores higher overall at 4.4 out of 5. The weights are published on how we rate, and so is the note about which of these is our paid featured partner.

The desk’s call

The board says PlexusDx. What the board cannot say is whether the advertised figures you were shown elsewhere match these — check the gap row, because a listing that advertises low and bills high will beat an honest one in any comparison built on advertised prices.

The verdict

On the board, PlexusDx at $189 a month is the more defensible choice on arithmetic alone. Willow earns its premium only if you will actually use what it does differently. Read the full reviews before deciding: PlexusDx and Willow.

How they sit against everyone else