Company domain change checker: find leads whose company rebranded or moved domains
In short: Opens each company domain's home page, follows the redirects and labels it moved to another domain, parked or for sale, not answering, or unchanged, then lists the same mailbox name at the new domain as a candidate. Limit: A redirect shows the website moved; it doesn't show where email went or whether any mailbox exists.
A company domain change checker finds the companies on an email list that rebranded, merged or moved to a new domain. Paste the list and each company domain's website is opened and its redirects followed: moved to another domain, parked or for sale, no website at all, or unchanged. For moved domains, the same mailbox name at the new domain is listed as a candidate to verify.
Price: this tool is free. Checking a whole email list is from $9/mo, and the first 100 checks are free with Google, no card. See pricing
Sample result
oldbrand.example now redirects to newbrand.example: the company moved.
- oldbrand.example
- Moved
- Old domain has MX
- Yes
- Candidate
- [email protected]
What this means for you
[email protected] is a candidate to check next to the old address.
- Redirects followed per domain
- Moved, parked or gone
- Old domain's MX shown
- Candidate at the new domain
- Rebrands
- Acquisitions
- CSV
By SimpleVerifier Team · Last updated
Old address or new one: which will deliver?
- An old domain often keeps taking mail for months after a rebrand, and a candidate at the new domain may not exist.
- Check both at /verify: a live mailbox check on every address, old and new.
- The first 100 email checks are free with a Google sign-in, no card.
How do I check if a company changed its email domain?
- Paste addresses one per line, or upload a CSV with an email column. Free mailbox addresses such as Gmail are skipped.
- Press Check the domains. Each unique company domain gets one guarded request to its home page and a DNS lookup; addresses stay in your browser.
- Read each domain's result, whether the old domain still has an MX record, and the candidate address at the new domain.
- Download every address labelled, or the addresses on parked and dead domains to suppress, then check the rest and the candidates.
Example
- You enter
- An email list with addresses at four company domains, one at
gmail.com. One company domain's home page answers 301 tohttps://www.newbrand.example/. - You get
- That domain is Website moved to another domain, newbrand.example, and
[email protected]gets the candidate[email protected]. The MX column shows whether oldbrand.example still has a mail server. The Gmail address isn't checked and goes straight to the list to verify. - Limits
- Up to 100 company domains a run without an account, 500 after a Google sign-in; free mailbox domains are skipped.
How do I know a company moved to a new domain?
Its old website sends you to the new one. When a company rebrands or is acquired, the old home page usually answers with a permanent redirect (HTTP 301 or 308, RFC 9110) to the new brand's site. The tool follows up to five redirects and compares the registrable domain it ends on with the one it started from; www. and other subdomains of the same domain don't count as a move. Redirects to a LinkedIn page or a site builder are labelled separately, because they don't name a new company domain.
Mail usually moves later than the website. The MX column shows whether the old domain still publishes a mail server: if it does, the old address may still deliver, or be forwarded; if it doesn't, mail to it will bounce. Domains that are parked, for sale or not answering at all point to a company that closed; the bulk website status checker shows the signals for each.
Is the candidate address at the new domain real?
It's a guess: the same mailbox name (jane.doe) at the new domain. Many companies keep their naming scheme when they move, and many don't, or give the new domain to only some staff. Check the candidates and the old addresses together before sending; if the candidate bounces, the bulk email permutator lists the other common formats for the name.
Is this faster than opening each website?
| This tool | Opening each site | |
|---|---|---|
| Domains per run | 100, or 500 signed in | One tab at a time |
| Redirect target compared | On the registrable domain | You read the address bar |
| Old domain's MX record | Shown | A separate lookup |
| Candidate address at the new domain | Built for every address | By hand |
Who uses this tool, and for what?
- Cold emailers
- Clean an old lead list of acquired and rebranded companies before a re-send.
- Agencies
- Update a client's account list after a year of mergers, with candidates at the new domains.
- Sales ops
- Find CRM accounts whose website now points to a parent company.
What can’t this tool tell you?
- A redirect shows the website moved; it doesn't show where email went or whether any mailbox exists.
- Candidate addresses are guesses built from the old mailbox name.
- Sites that block automated requests show as no answer or an HTTP error.
- 100 domains a run without an account, 500 after a Google sign-in.
Common questions
- How do I find out if a company changed its email domain?
- Open its old website. If it redirects to a different domain, the company has most likely moved, and its email usually follows. This tool does that for every company domain on a list and shows whether the old domain still takes mail.
- Will email to the old domain still work?
- Sometimes. Many companies keep the old domain's MX record for a while and forward mail. The MX column shows whether the old domain still has a mail server; a mailbox check shows whether the address itself still delivers.
- Where does the candidate address come from?
- It's the same name before the @ at the new domain. It isn't looked up anywhere, so treat it as a guess until a mailbox check confirms it.
- Why are Gmail addresses skipped?
- Free mailbox providers don't change domain, so there's nothing to check. They're carried through to the mailbox check at the end.
- Are my addresses uploaded?
- No. Only the unique company domains are sent; the addresses stay in your browser.
Sources
A tidy list can still be full of dead addresses.
Extracting, deduplicating and syntax checks all work on the text of an address. None of them can tell whether the mailbox exists. Only the server that hosts it can answer that, through an SMTP check, and that is what the paid product does.
- Upload the cleaned file as it is: CSVs up to 100,000 rows
- A real SMTP mailbox check on every row, with catch-all detection
- Small list? Starter at $9/mo covers 2,500 emails a month, cancel anytime
Plans from $9 a month, cancel anytime, no contract. Sign in with Google and your first 100 email checks are free, no card. The free tools stay free either way.