How often should I check my domain reputation?

Monthly for a full audit, and after any significant change: a new sending platform, a large campaign, a domain migration, or a suspected compromise. Spam rate is worth watching weekly if you send at bulk volume, because it moves faster than anything else.

Can a single spam complaint hurt my reputation?

No. Complaint rate is proportional, so one complaint against a large send is noise. What matters is the ratio: sustained rates above 0.1% harm bulk-sender delivery, and 0.3% is the threshold that costs you mitigation eligibility.

Does buying a fresh domain fix a bad reputation?

It resets history rather than fixing the cause. A new domain has no reputation, must be warmed up from zero, and earns the same reputation within weeks if the list and content are unchanged. Repair the existing domain instead.

Does a subdomain inherit the parent domain's reputation?

Partly, and not symmetrically. A new subdomain benefits from a parent with good standing, but a subdomain that behaves badly can drag the parent down. This is why transactional and marketing mail belong on separate subdomains — it contains the damage.

Does DMARC at p=none improve reputation?

Not by itself. It satisfies Google's DMARC requirement for bulk senders and it gives you reports, both of which are valuable — but it instructs receivers to take no action on failures, so it stops nobody from spoofing you. The reputation benefit comes at p=quarantine and p=reject. Check where your domain stands with the DMARC checker.

How can you check and improve your email domain reputation?

Your email domain reputation decides whether your messages reach the inbox or land in spam. Each mailbox provider builds it independently from how recipients react to your mail — and unlike a credit score, there is no single number you can look up.

This guide covers what feeds reputation, the thresholds Google and Yahoo publish, which tools still report what, and how to repair a domain that has slipped.

What exactly is domain reputation?

Mailbox providers score your sending domain on observed behaviour and use that score to decide inbox placement. The signals that matter most:

Spam complaint rate — recipients clicking "report spam". The single strongest negative signal.
Spam trap hits — mail to addresses that exist only to catch senders with poor list hygiene.
Engagement — opens, replies, and messages moved out of spam all read as positive; deletions without opening do not.
Volume consistency — a sudden spike from a domain with no sending history looks like a compromised account.
Authentication — mail that fails SPF, DKIM, and DMARC gives providers no identity to attach reputation to.

Reputation is per-provider. Gmail's view of your domain is not Microsoft's, and a clean bill of health from one says nothing about the other.

The thresholds Google and Yahoo actually publish

This is where most advice goes wrong, so the numbers are worth stating precisely.

Google's sender guidelines tell bulk senders to keep the spam rate reported in Postmaster Tools below 0.10%, and to prevent it from ever reaching 0.30%. Those are two different numbers doing two different jobs: 0.1% is the target you operate under, and 0.3% is the ceiling you must never touch. Google states that rates above 0.1% already harm inbox delivery for bulk senders, and that rates of 0.3% or higher hurt considerably more.

There is a further consequence. Since June 2024, bulk senders with a user-reported spam rate greater than 0.3% are ineligible for mitigation — meaning Google will not intervene to help with delivery problems. Eligibility returns once the rate stays below 0.3% for seven consecutive days.

A "bulk sender" is anyone sending more than 5,000 messages per day to Gmail accounts. Yahoo publishes an equivalent regime.

Bulk senders must also publish SPF and DKIM and DMARC — all three. Lower-volume senders need only SPF or DKIM. Marketing and subscription mail must support one-click unsubscribe, and Google recommends honouring unsubscribe requests within 48 hours.

How to check your domain reputation

No tool gives you "your" reputation, because no such single value exists. What you can do is read the signals each provider exposes.

Google Postmaster Tools reports your Gmail spam rate, authentication results, delivery errors, and a compliance status against the sender guidelines. Note that the Domain Reputation and IP Reputation dashboards were retired with the move to Postmaster Tools v2 — the v2 API carries over all v1 functionality except domain and IP reputation. Spam rate and compliance status are now the metrics to watch. If you are following an older guide that tells you to check your "domain reputation" here, that screen no longer exists.
Microsoft SNDS (Smart Network Data Services) exposes complaint and trap data for Outlook.com. It is keyed to IP addresses, not domains, so it is only useful if you send from your own dedicated IPs.
Sender Score rates IP reputation on a 0–100 scale — it is not a domain score, despite how it is often described. It is operated by Validity and free to check.
Cisco Talos reports reputation for both IP addresses and domains.
Spamhaus runs the DBL domain blocklist alongside its IP lists; check both at their reputation checker.
Palisade checks the authentication half of the picture. The Email Security Score tool grades your SPF, DKIM, and DMARC configuration, and the domain reputation and IP reputation tools check blocklist status.

A step-by-step reputation audit

Validate authentication first. Nothing else matters if providers cannot identify you. Confirm SPF, DKIM, and DMARC all pass and align — see what are DMARC, DKIM, and SPF for how alignment works.
Read your Gmail spam rate. In Postmaster Tools, check it against the 0.1% target, not the 0.3% ceiling.
Check blocklists for both your domain and your sending IPs.
Enrol in provider tooling. Postmaster Tools for Gmail; SNDS for Outlook.com if you run dedicated IPs.
Read your DMARC reports. They reveal sources sending as your domain that you may not know about — including attackers. Understanding DMARC reports covers the format.
Track your own metrics. Complaint rate, bounce rate, and unsubscribe rate map to reputation. Watch their trend against your own baseline; no published industry number tells you what a healthy open rate looks like for your list.

Warning signs of a damaged reputation

Spam rate climbing toward 0.1% in Postmaster Tools.
A sharp drop in delivery or engagement rates with no change in content.
Unexpected SPF, DKIM, or DMARC failures appearing in reports.
Appearance on any blocklist.
Mail to one provider landing in spam while another still inboxes it — reputation is per-provider, and this is what a localised problem looks like.
Sending volume spikes at odd hours, which often means an account has been compromised.

How to improve your domain reputation

Authenticate completely, then enforce. Publish SPF, DKIM, and DMARC. A DMARC record at p=none satisfies Google's requirement but blocks nothing — move to p=quarantine and then p=reject once your reports show legitimate mail passing.

DMARC record — monitoring vs enforcement

Cut the complaint rate at the source. Use confirmed opt-in, make the unsubscribe link obvious, and honour unsubscribes within 48 hours. A prominent unsubscribe link lowers complaints, because the alternative recipients reach for is the spam button.

Practise list hygiene. Remove hard bounces immediately and suppress addresses that have not engaged in months. Old addresses get recycled into spam traps, and a trap hit is far more damaging than a low open rate.

Warm up new domains and IPs gradually. Reputation is built on history. A brand-new domain sending at volume on day one looks exactly like an attacker.

Separate your mail streams. Send transactional mail (receipts, password resets) from a different subdomain than marketing. A bad campaign then cannot take your password-reset mail down with it.

Fix blocklist entries properly. Follow the provider's removal process, but find the cause first. Delisting without fixing the cause gets you relisted, and repeat listings are harder to clear.

Common issues with domain reputation

Why has my domain reputation dropped when nothing changed?

Something changed, but probably not on your side of the send. Check whether a list was imported, a campaign was resent to unengaged recipients, or a vendor changed sending infrastructure. Also check your DMARC reports for sources you do not recognise: if someone is spoofing your domain, their complaints attach to your reputation. This is the case for moving DMARC to enforcement rather than leaving it at p=none.

Why can't I find domain reputation in Google Postmaster Tools any more?

Because it is not there. The Domain Reputation and IP Reputation dashboards were retired in the move to Postmaster Tools v2, and the v2 API covers everything the v1 API did except those two. Use the spam rate and compliance status screens instead — Google still tracks reputation internally, it simply no longer shows you a score for it.

Why is my mail inboxing at Gmail but going to spam at Outlook?

Because each provider maintains its own reputation model, on its own data. A Gmail-clean domain can be poorly regarded at Outlook.com, particularly if most of your complaints come from Microsoft mailboxes. Enrol in SNDS to see Microsoft's view; a Postmaster Tools screenshot tells you nothing about it.

Why is my spam rate fine but my mail still lands in spam?

Spam rate is one signal among several. Check that SPF, DKIM, and DMARC pass and align — an authentication failure gives providers no identity to attribute your good history to. Then check blocklists, and check whether the affected mail comes from a subdomain or vendor with no sending history of its own. A DMARC report will show which source is failing.

Why did our reputation collapse after a single campaign?

Because complaint rate is a rate. Sending one large campaign to a stale, unengaged list generates a spike of complaints against a modest volume, which can push the ratio past 0.3% in a day. Recovery is possible — Google restores mitigation eligibility after seven consecutive days below 0.3% — but the fix is to stop mailing unengaged addresses, not to wait it out.