Auto-reg (FB autoregs) is a freshly registered empty account created by software or a service. It has zero history, no activity, no friends. You get it cheap because it's brand new and carries minimal trust from the platform.
Self-reg is an account registered by hand—a real person signed up, maybe added a profile picture, spent some time on it. It looks more human from the start, even if it's still new.
The key difference: self-reg has manual touches that make it appear less robotic. Auto-reg is stripped down and needs work before you can push ads through it.

Trust level out of the box
Auto-regs start with basically zero trust. Facebook sees a brand new account with no history, no friends, no activity. The platform flags new accounts for extra scrutiny—it's standard security.
Self-regs have a slight edge. Because a human registered it and maybe spent time on it, the account doesn't look like it rolled off an assembly line. It still needs warming, but it starts from a better position.
Neither format comes with built-in credibility. Both need work. The difference is how much.
Warming and prep time
Auto-regs need more sessions before they're ready to run ads. You're building trust from scratch—adding friends, scrolling the feed, interacting with content, watching ads in your feed. This takes 20+ sessions of warming to reach a state where the account won't immediately flag ads as suspicious.
Self-regs need fewer sessions. They've already got some baseline activity baked in, so you can often move faster. Still need warming, but the runway is shorter.
Time matters when you're billing. If you need an account live in days, not weeks, self-reg saves you time.
Cost and first billing
Auto-regs are cheaper upfront. You pay less per account because you're buying raw material—no prep work has been done. The seller hasn't invested time in warming or aging.
Self-regs cost more because someone already put in the work. The account is closer to ready.
For first billing, this matters. If you're testing a campaign and need to move fast, the extra cost of self-reg might be worth it. If you're building a farm or have time to warm accounts properly, auto-reg saves money.
Which to choose for first billing
If you've never billed on Facebook before: take self-reg. You get a small trust buffer, need less warming, and reduce the risk of the account getting flagged while you're still learning the platform's behavior. The extra cost is cheap insurance against starting with a brand new account that Facebook immediately suspects.
If you're experienced and have a warming workflow: auto-reg works fine. You know how to age accounts properly, you have the time, and you save money per account.
If you need to bill in the next few days: self-reg. Auto-regs need more sessions before they're ready, and rushing that process increases the chance of a check or block.

Aging and history
Self-regs can come with account age (aging)—the account was registered weeks or months ago and left untouched to build passive trust. This is valuable. An account that's been sitting for 90+ days looks more legitimate than one created yesterday.
Auto-regs are fresh off the line. They have no age. You're starting the clock the moment you buy them.
For first billing, aged self-regs are the safest choice. The account has time behind it, a human registered it, and it's ready to work with minimal prep.
What to look for when buying
Check the account age in the product description. Look for self-regs with 90+ days or older—these carry real value.
See if 2FA is included. It's not essential for billing, but it adds another layer of control.
If the description says the account has been warmed (20+ sessions), that's a green flag. You're buying something closer to ready.
For auto-regs, the price should be significantly lower. If it's almost the same as self-reg, there's no reason to take the extra risk.

Common mistake: thinking auto-reg is faster
Buyers often assume auto-reg is quicker because it's cheaper. Wrong. Cheap auto-regs need more work before billing. You save money per account but spend time warming. Self-reg costs more upfront but gets you to billing sooner.
Choose based on what's scarce for you: time or budget. Short on time—self-reg. Short on budget—auto-reg with a solid warming plan.