How our affiliate links work

An affiliate link is a link to a seller that pays us a commission if you buy something after clicking it. You do not pay anything extra to us for using one.

Current status

Right now, none of the links on b12guide.com are affiliate links. Every product link goes straight to the seller's official page, and we earn nothing if you buy. We plan to add affiliate links later. When we do, this section and the affected pages will say so.

How we are funded

Our content is free to read. If we add affiliate links, the site will be funded by commissions from testing services and dietary supplements. Sellers cannot pay to be included or ranked. The affiliate links will point to two kinds of products: vitamin B12 testing services, such as at-home kits and lab tests you order online, and dietary supplements. The seller pays the commission. We do not add any charge to the price the seller sets.

Commissions do not decide our content

We do not choose which products to include, or the order they appear in, based on how much commission they pay. Test kits are ordered by price. Sellers cannot pay to be listed, ranked, or described more favorably, and they do not see our pages before they are published. Every product detail we show comes from the seller’s own page, with the date we checked it. When we cannot confirm a detail, we say so instead of guessing.

How to recognize an affiliate link

Affiliate links appear as “Check price” buttons in our product cards and comparison tables, with the label “Affiliate link” right next to them. Pages that contain affiliate links also show a short disclosure near the top. In the page code, each affiliate link carries the rel=“sponsored” tag, which tells search engines it is a paid link. Links labeled “View test details” are plain links to the seller and earn us nothing.

Prices and availability

Prices and stock are set by the seller and can change at any time. We show U.S. prices with the date we last checked them. The seller’s page is always the final word, so confirm the price and details there before you buy.

Not an endorsement

We do not make or sell any product. Your order, shipping, refunds, and customer service are between you and the seller, and we are not responsible for how a seller handles them. A listing on our site is not a recommendation that a product is right for you; that is a question for your clinician.

How this page was prepared

Our privacy policy and affiliate disclosure were written with reference to the FTC Endorsement Guides (16 CFR Part 255), the California Online Privacy Protection Act (CalOPPA), the California Consumer Privacy Act as amended by the CPRA (CCPA), and the Children's Online Privacy Protection Act (COPPA). A member of our editorial team checked each statement by hand against how the site actually works.

Content without commissions

Our explanations of symptoms, lab results, and causes carry no affiliate links, and they follow the same sourcing rules as our product comparisons. Read how we choose sources in our editorial policy, and send questions through our contact page.