https://www.rascalandfriends.us/samplepacksusa -fill out the form to get Free Rascal + Friends Diaper Samples. First 10,000.

https://app.sampler.io/milliemoon -register or login with your Sampler account for a chance to get Free Millie Moon Luxury Diapers

https://www.neocate.com/shop/request-samples-consumer.aspx -fill out the form to get a Free Neocate Baby Formula Sample.

https://www.enfamil.com/toddler-sample-request/ -fill out the form to get a Free Enfagrow Toddler Formula Sample. –Update – still available

https://www.sendmeasample.net/else -register and install either the Alexa Skill or the Google Assistant Skill here(depending on which voice assistant you use).  Once you do that, say “Ask Send Me a Sample for Else” and go through the steps to request it.  If you want to use Alexa, you can download the Amazon app here. It should show up in your order history here when you’re done. 
-Update- you can go here and request the sample without doing the voice command.

https://www.rascalandfriends.us/samplepacksusa -fill out the form to get Free Rascal + Friends Diaper Samples. First 10,000.

https://www.cuties.com/where-to-buy/free-samples -enter your email and click the link in your email to request a Free Cuties Diapers Sample. –Update -working again with all sizes but they usually run out fast.

https://mymilliemoon.com/request-a-sample/ -scroll down and fill out the form to get Free Millie Moon Diaper Samples.

https://fttnewstandard.com/ -scroll down and fill out the form to get a Free Nutricia Fortini Infant Formula Sample. “Fortini is indicated for term infants from birth up to 18 months of age (or 19.8 lbs/9 kg) with or at risk of growth failure, increased energy requirements, and/or fluid restrictions due to conditions such as congenital heart disease, chronic lung disease, respiratory syncytial virus, neurological syndrome or neuro-disabilities, cystic fibrosis and non-disease-related FTT.”