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Migrating to AtData’s SafeToSend® API from FreshAddress

Help Center   ❯  AtData Services   ❯  Email Verification

Why migrate?

AtData’s SafeToSend® service is where the company is adding new functionality and focusing future Product & Engineering efforts. In order to take advantage of existing enhancements and future upgrades, you’ll need to migrate to AtData SafeToSend.

By upgrading to AtData’s SafeToSend Email Verification and Hygiene, you’ll benefit from:

*Please note that Engagement Score is included for free in SafeToSend for all AtData subscription customers.

The key differences between the legacy FreshAddress and AtData’s SafetoSend API are changes to the email response codes returned with your validation data. Whereas FreshAddress provides results using findings and comments, AtData SafeToSend describes results with a status and a numerical status code as shown in the API response of both services below.

FreshAddress SafeToSend AtData SafeToSend
“EMAIL”: “[email protected]”,
“COMMENT”: “invalid email account”,
“SUGG_COMMENT”: “suggestion not SafeToSend”,
“ERROR_RESPONSE”: “The email address you entered cannot be registered”,
“ERROR”: “”,
“UUID”: “67e1d87b-730d-4029-a086-dbbcd18667b9”
“safe_to_send”: {
“status”: “invalid”
“status_code”: 400,
“address”: “[email protected]”,
“domain_type”: “biz”,

AtData SafeToSend Statuses – Quick Summary:

Compare the above statuses to those found in the FreshAddress SafeToSend:

Since the AtData status codes are numerical values, all references to FreshAddress comments or comment codes must be updated when migrating to AtData SafeToSend.

In some cases, there are direct matches for individual codes. For example:

Also, AtData’s SafeToSend provides detailed list of invalid codes (codes 100-520). 

Some of these match with FreshAddress codes fairly neatly.  For example, error codes A1, A2, A3, A4, C1, CC, DT, LN, ML, P2, P3, P4, P5 in FreshAddress are covered by invalid codes 100-215 in AtData’s SafeToSend. However, some of the FreshAddress “Warning” codes are also considered “invalid” in AtData’s SafeToSend.

To make this easier to understand, below is a detailed breakdown of how all the statuses compare in the AtData SafeToSend Output vs the legacy FreshAddress output:

AtData SafeToSend Output   FreshAddress SafeToSend Output
Status Code Description   Status Code(s) Description
unknown 5 Timeout. Did not get a response in time.   valid V valid – The email address passed the majority of our SafeToSend process however it cannot be 100%  confirmed as deliverable and thus is not subject to our deliverability guarantee.
valid 10 Syntax OK.  
valid 20 Syntax OK and the domain is valid.  
catchall 45 Domain is a catch all and does not support validation.  
safetosend 50 valid – SafeToSend – The email address passed 100% of the SafeToSend process. Subject to deliverability guarantee.   valid (STS) VS valid – SafeToSend – The email address passed 100% of the SafeToSend process. Subject to deliverability guarantee.
valid 55 Address is allowed by client-configured exceptions   valid CO/CE customer override
invalid 100 General syntax error.   E – Error A1, A2, A3, A4, C1, CC, DT, LN, ML, P2, P3, P4, P5 Various invalid error: missing domain, multiple @,bad character ,double .com ,bad length,contains multiple typos,ends with period,period following @,starts with a period, etc….
invalid 110 Invalid character in address.  
invalid 115 Invalid domain syntax.  
invalid 120 Invalid username syntax.  
invalid 125 Invalid username syntax for that domain.  
invalid 130 Address is too long.  
invalid 135 Address has unbalanced parentheses.  
invalid 140 Address doesn’t have a username.  
invalid 145 Address doesn’t have a domain.  
invalid 150 Address doesn’t have an @ sign.  
invalid 155 Address has more than one @ sign.  
invalid 200 Invalid top-level domain (TLD) in address.  
invalid 205 IP address is not allowed as a domain.  
invalid 210 Address contains an extra space or character.  
invalid 215 Unquoted spaces not allowed in email addresses.  
invalid 255 Address is not allowed by client-configured suppressions   W – Warning XC client restricted – Email address matches an entry on client provided suppression.
invalid 310 Domain doesn’t exist.   W – Warning DC, XH bad domain DC  Email address is associated with a domain with inactive mail servers. bogus XB NO Email address with a restricted handle and/or domain; error XH Email address failed a domain specific rule, e.g. does not allow underscores in the address handle.
invalid 315 Domain doesn’t have a valid IP address.  
invalid 325 Domain can’t receive email.  
invalid 400 Mailbox doesn’t exist.  
invalid 410 The mailbox is full and can’t receive email.  
invalid 420 Mail isn’t accepted for this domain.  
invalid 500 Emails with that username aren’t accepted.  
invalid 505 Emails with that domain aren’t accepted.  
invalid 510 That address isn’t accepted.   W – Warning B invalid email account B  Email address failed FreshAddress’s deliverability check.
invalid 515 Address was rejected during our manual review process        
invalid 520 Address matched to known bouncers (optional feature).        
trap 525 Address is a spamtrap, a known complainer or is suppressed.   W – Warning XP, XF problematic or frequent complainer - Email address is considered as problematic – includes spamtraps and potentially toxic addresses. role account XR NO Email addresses such as sales@, info@ and webmaster@. frequent complainer XF Email address owner is known to submit spam/abuse complaints.or
risky 530 Address has opted out from commercial email.        
risky 535 Address is on ANA’s “Do Not Email List”   W – Warning XE EMPS suppression XE  Email addresses belonging to DMA’s “Do Not Email List”
unknown 999 System error.        
        W – Warning XW FCC wireless XW  Email address originates from an FCC wireless domain.

Files and Delivery Methods

File Delivery methods:

FreshAddress supports:

1) FreshAddress Portal
3) Real-time API

AtData SafeToSend supports:

1) InstantData Portal 
3) Real-time API
4) List API

File Contents:

AtData’s SafeToSend adds six fields to your email list: 

Compared to FreshAddress SafeToSend which includes the following fields:

API Comparison

FA API Output: 

Example API Call & Result (w/ suggestion)
GET https://[REQUEST URL]&[email protected]
“EMAIL”: “[email protected]”,
“COMMENT”: “valid”,
“SUGG_EMAIL”: “[email protected]”,
“ERROR”: “”,
“UUID”: “be6190ec-9a2d-4ca7-9e6a-5b3455838f8e”

AD STS API Output:

Invalid Email Request with Correction


“safe_to_send”: {
“status”: “invalid”,
“status_code”: 155,
“address”: “info@@atdata,com”,
“role_account”: true,
“email_corrections”: [
[email protected]

If you have additional questions regarding AtData’s SafeToSend, we encourage you to review our full SafeToSend documentation or contact us via customer support.