---
title: "SPF=Fail, but the recipient’s mailbox has not quarantined or rejected the email- why? | DuoCircle"
description: "SPF=fail, but the recipient’s mailbox has not quarantined or rejected the email- why?"
image: "https://www.duocircle.com/images/og-default.png"
canonical: "https://www.duocircle.com/blog/email-security/spf-fail-why-was-email-not-quarantined-or-rejected/"
---

Quick Answer

An SPF=fail result does not always trigger rejection because antispam systems treat SPF as one signal, not the final verdict. Common reasons a failing message still gets delivered: the SPF record uses \~all (soft fail) instead of -all (hard fail), so receivers are told to be cautious rather than block; DMARC is at p=none, so receivers monitor failures but take no enforcement action; DKIM passes and aligns, satisfying DMARC even when SPF fails; the receiver weighs sender reputation, content, and engagement signals heavily and lets a known good sender through; or the receiver applies forwarding-related leniency. To enforce on failure, set SPF qualifier to -all, publish DMARC at p=quarantine or p=reject, and ensure DKIM signs all legitimate mail so authentic forwarded messages still pass.

SPF=Fail, but the recipient’s mailbox has not quarantined or rejected the email- why?

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![What is a DMARC](https://media.mailhop.org/duocircle/images/2024/08/what-is-a-dmarc-7616.jpg) 

When an email shows ‘SPF=fail’ but is not blocked by an antispam filter, it can be due to several reasons. Knowing and **fixing the issue** is important; otherwise, [threat actors](https://thehackernews.com/2024/07/tag-100-new-threat-actor-uses-open.html) can exploit the security gap by sending fraudulent emails in your business’ name. 

## SPF misalignment tolerance

Sometimes, SPF’s result is not considered a definitive indicator due to a few reasons-

### Antispam systems settings

_Antispam systems and tools are designed to consider several factors before tagging an email as ‘safe’ or ‘unsafe_.’ Also, these systems are configured to be more lenient with SPF, which means they consider SPF’s result to be ‘one of the indicators’ and not ‘the most **definitive indicator**.’ If other indicators, like [DKIM checks](/resources/dkim-checker), DMARC checks, content analysis, [sender reputation](https://www.forbes.com/councils/forbescommunicationscouncil/2019/07/23/improve-your-email-sender-reputation-in-three-steps/), rule-based filter, blocklist filter, etc., are favorable, the email won’t be quarantined or rejected by the recipient’s mailbox.

[![](https://media.mailhop.org/duocircle/images/2024/08/spf-validator-7.jpg)](https://media.mailhop.org/duocircle/images/2024/08/spf-validator-7.jpg)

### Soft fail policy

 The SPF record might be set to \~all (softfail) instead of -all (fail). A soft fail instructs the recipient’s [mail server](https://www.techtarget.com/whatis/definition/mail-server-mail-transfer-transport-agent-MTA-mail-router-Internet-mailer) not to strictly disallow a [suspicious email](https://www.darkreading.com/cloud-security/new-dmarc-data-shows-75-increase-in-suspicious-emails-hitting-inboxes) from entering the mailbox but instead suggests that such emails should be treated with caution. [Antispam tools](/spam-filtering/stop-spam-in-its-tracks-with-superior-anti-spam-tools/) may allow these **sorts of messages** to pass through depending on the criteria. 

## DMARC policy

If a domain has a [DMARC policy](/resources/dmarc-policy) in place that is set to **p=none**, the policy is only monitoring and not enforcing strict rejection. Even if the SPF check fails, the DMARC policy doesn’t require the email to be blocked.

DMARC also **requires alignment** between the [SPF](/resources/what-is-spf) domain and the FROM address domain. If the alignment fails but the DMARC policy is set to p=none, the email is not blocked.

## Sender reputation

Some **antispam filters** weigh the reputation of a sender domain or [IP address](https://en.wikipedia.org/wiki/IP%5Faddress) more heavily than the SPF results. That’s why if a potentially [fraudulent email](https://apnews.com/article/technology-travel-business-crime-cybercrime-2f050130524aae7641da7005ecc02562) is sent from a domain with a high reputation, it will likely pass through even with an SPF fail. This might not always be a key factor, but many tools still rely on it. 

## Multiple SPF checks

There should only be one SPF record per domain. Having more than one [SPF record](https://support.dnsimple.com/articles/spf-record/) is technically incorrect, but it happens in practice. So, if this is the case with your domain, then some systems may incorrectly parse or apply the **SPF mechanism**, especially if these records contradict each other. This leads to a failure in SPF validation without resulting in a block.

If you also have multiple SPF records corresponding to your domain, consider [merging them into one](https://autospf.com/blog/merge-spf-records-to-fix-multiple-spf-records-error/). 

[![email security](https://media.mailhop.org/duocircle/images/2024/08/check-dmarc-record-3955.jpg)](https://media.mailhop.org/duocircle/images/2024/08/check-dmarc-record-3955.jpg)

## Fallback mechanisms

[Fallback mechanisms](https://fastercapital.com/keyword/fallback-mechanisms.html) are the **additional checks and security measures** used by antispam tools for a more nuanced evaluation of an [email security](/) and authenticity. _These include monitoring factors like the volume of emails sent, the frequency of emails sent to specific recipients, and historical data on how recipients interact with these emails (e.g., high engagement rates)_.

Also, if the **recipient whitelists a sender**, the tool may disregard the [SPF failure](/content/spf-permerror/spf-fail) and let the email through. 

While not all the issues can be fixed at your end, try working around the ones emerging from your lack of **attention or knowledge**. For any help, [contact us](/contact).

## Topics

DKIMDMARCemail securityspfSPF record 

![Brad Slavin](https://media.mailhop.org/dmarcreport/images/team/brad-slavin.jpg) 

Brad Slavin 

General Manager

General Manager at DuoCircle. Product strategy and commercial lead across the email security portfolio.

## Secure your email infrastructure

Protect, authenticate, and deliver. Contact our team to find the right solution.

[Contact Sales](/contact/) [Explore Products](/products/) 

## Related Articles

[  Email Security 6m  Building a zero-trust security model for emails  Dec 11, 2024 ](/blog/email-security/building-a-zero-trust-security-model-for-emails/)[  Email Security 7m  How email authentication helps you prove sender identity under ISO 27001  Nov 18, 2025 ](/blog/email-security/how-email-authentication-helps-verify-sender-identity-for-iso-27001/)[  Email Security 6m  How do you achieve SPF alignment to enhance email security and deliverability?  Mar 25, 2025 ](/blog/email-security/how-spf-alignment-improves-email-security-and-deliverability/)[  Email Security 3m  How SPF, DKIM, and DMARC quietly protect every email you send?  Jun 13, 2025 ](/blog/email-security/how-spf-dkim-dmarc-protect-every-email-you-send-securely/)

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