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Official form guide
Form 15100-SP: 15100 (sp)
Department of the Treasury - Internal Revenue Service Form 15100 (sp) is a request for an extension of Taxpayer Identification Number in adoption process (ATIN). This form is used when adopting children and must be submitted to the IRS.
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IRS Form 15100-SP - 15100 (sp)
Department of the Treasury - Internal Revenue Service Form 15100 (sp) is a request for an extension of Taxpayer Identification Number in adoption process (ATIN). This form is used when adopting children and must be submitted to the IRS.
Risk Radar
Scan points- 1Ensure you correctly select the circumstance that matches your adoption status on Form 15100 (sp).
- 2Filing without completing all required fields in the header section.
- 3Not indicating which circumstance applies to the adoption (e.g., SSN received vs. extension needed).
- 4Forgetting to write or print the name on the signature lines at the bottom of Form 15100 (sp).
- 5Failing to provide a reason when selecting an option that requires one.
Plain English
This form lets you ask the IRS for more time while your child's Taxpayer Identification Number is being set up. You use it because you have received a Social Security number, or you need an extension for one that is already assigned (ATIN).
Submission Date
- Filing date: 2022-06-09 22:10:27
- Preparation window: collect IDs, supporting records, and signatures in advance.
- Final review: verify names, dates, and required fields before submission.
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What this form is for
- Use this form when requesting an extension of a Taxpayer Identification Number in the adoption process (ATIN) for children.
- Do not use this form when you already possess the necessary identification number or are filing another type of tax document related to adoption.
- Check Form 15100 instead when applying for an ATIN extension through the main application process.
Form selector
Use this form or another form?
Received a Social Security Number (SSN) for the adopted child
The form requires you to list the assigned SSN in the designated field.
✓ Confirm the correct SSN is listed.
Need one-year ATIN extension and have an assigned ATIN
You must specify that a year's extension is needed and provide the existing ATIN number.
✓ Ensure both names/ATIN fields are populated correctly.
Cannot obtain an SSN for the adopted child (No SSN)
This situation requires documenting why the SSN could not be obtained while requesting the extension.
✓ Verify the reason for not obtaining the SSN is clearly stated.
Deadline or filing window
The form allows the filer to request an extension of one year for a child's Taxpayer Identification Number (ATIN). The specific deadline is not stated, but filing this form initiates the request process.
Checklist
What you need before filling it out
Type of Request
Check box selection for one circumstance · All sections on p.1
Adoption Status
Select definitive, pending, or attach documents · Boxed section below circumstances
Parent Information
Name and Signature for both parents · Bottom signature lines
Mailing Address
Your new address (if changed) · Top section after identification fields
ATIN/SSN Details
Assigned Number for each scenario · Fields next to circumstance boxes
Before you submit
- 1Fill out all required fields on Form 15100 (sp) completely.
- 2Indicate exactly which circumstance applies by checking one box in the designated area.
- 3If applicable, write your new address clearly at the top of the form.
- 4Provide the Name and SSN/ATIN for each listed individual.
- 5Select the appropriate Adoption Status (Definitive or Pending).
- 6Sign and date the form as both adoptive parents.
- 7Keep a copy of the completed Form 15100 (sp) for your records before mailing or faxing.
How to file this form
- 1Complete all personal information fields, including names, identification numbers, and contact details on Form 15100 (sp).
- 2Indicate the specific circumstance that applies to your adoption request by checking the corresponding box.
- 3Sign and date the form as both adoptive parents in the designated signature areas.
- 4Mail or fax the completed Form 15100 (sp) to the Internal Revenue Service, ensuring you retain a copy for proof of filing.
Known limitations
- 1The form applies to situations where an adoption is pending.
- 2The form applies when a Taxpayer Identification Number (TIN) has been assigned, but it is still in the process of adoption (ATIN).
- 3The form applies for requests related to children who have received a Social Security number.
- 4The form applies when an adoption is final.
Field map
Compact field-by-field guide
General Info
2 items
Full legal name and taxpayer identification number (SSN or EIN).
Current mailing address.
Details
2 items
Complete all applicable sections of this form according to the official IRS instructions.
Enter the relevant dollar amount if this form involves tax calculation.
Certification
1 items
Read and acknowledge any certifications required by this form.
Signatures
1 items
Sign and date. Unsigned forms cannot be processed.
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Fillable formOpen in Editor->The current edition of IRS Form 15100 (sp) is dated October 2017 (Rev. 10-2017). The source does not point to a page indicating the absolute latest revision, but it provides specific contact and mailing details for this version.
What changed or needs a fresh check
- Edition date — confirm the revision date reads 10-2017.
- Fee — Not stated in the official source
- Mailing address — confirm standard delivery to Internal Revenue Service Stop 6182, Austin, TX 73301-0066.
- Signature — confirm both adoptive parents sign and date the form.
- Form Number — confirm the document reads Form 15100 (sp) Catalog Number 93086C.
Quick Facts
Downloads
After you file
- 1Retain a copy of the completed Form 15100 (sp) after submitting it.
- 2If you change your address, write the new address on the form before sending it.
- 3The form can be submitted via postal mail or fax to specific IRS locations.
- 4Contact the Internal Revenue Service at (737) 800-5511 if questions arise.
Sources
- SRCForm 15100 (sp) is titled 'Solicitud de prórroga del Número de identificación del contribuyente en proceso de adopción ( ATIN )' on page 1.
- SRCThe form was revised in October 2017, with the current edition listed as 10/17 on page 1.
- SRCStandard mail submission is to Internal Revenue Service Stop 6182 Austin, TX 73301-0066 on page 1.
- SRCNext-day delivery submission is to Internal Revenue Service 3651 S. Interregional Hwy 35 Stop 6182 Austin, TX 78741 on page 1.
- SRCThe fax number provided for the form is (855) 250-1731 on page 1.
- SRCQuestions regarding Form 15100 (sp) can be directed to the Internal Revenue Service at (737) 800-5511 on page 1.
Common confusion points
What is ATIN?
ATIN
This stands for Adoption Taxpayer Identification Number and is used when a TIN is in process.
→ Check the box corresponding to 'Necesito una prórroga de un año para (Nombre del hijo adoptado) ATIN (ATIN asignado)' if this applies.
When should I use Form 15100 (sp)?
Form 15100 (sp)
Use it when requesting an extension of a Taxpayer Identification Number during the adoption process.
→ Verify that your situation matches one of the listed circumstances on page 1.
Do I need to fill out all fields if my child has already received a Social Security number?
No, you only select the circumstance(s) that apply (e.g., 'Recibí un número de Seguro Social para...').
Ensure you provide the SSN in the corresponding field.
What is the difference between filing by mail and fax?
Filing method
The form can be sent via standard mail or next-day delivery to different IRS addresses.
→ Confirm which service center address matches your desired submission speed.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- Not stated in the official source — verify on the agency site (Contacting the IRS at (737) 800-5511 is listed as a way to address issues).
Questions about IRS Form 15100-SP
What is IRS Form 15100-SP used for?
This form lets you ask the IRS for more time while your child's Taxpayer Identification Number is being set up. You use it because you have received a Social Security number, or you need an extension for one that is already assigned (ATIN).
Who must file IRS Form 15100-SP?
Parents adopting children must file Form 15100 (sp) with the Internal Revenue Service.
What information does IRS Form 15100-SP require?
The form collects basic contact information under the header, and then asks which circumstance applies regarding a child's Social Security number or ATIN. It also requires signatures from the adoptive parents at the end.
Where do I file IRS Form 15100-SP?
For standard mail delivery, send Form 15100 (sp) to Internal Revenue Service Stop 6182, Austin, TX 73301-0066. For next-day delivery, use the address: Internal Revenue Service 3651 S. Interregional Hwy 35 Stop 6182, Austin, TX 78741.
How do I complete IRS Form 15100-SP?
First, fill out the header with your identifying and contact details. Next, indicate which circumstance applies from the provided list—such as receiving a Social Security number or needing a one-year extension. Finally, complete the signature lines for both parents.
What happens if IRS Form 15100-SP is filed incorrectly?
If information is incorrect or missing, it may cause delays in the IRS processing your request for an extension of the Taxpayer Identification Number (ATIN).
ATIN — what should I check?
This stands for Adoption Taxpayer Identification Number and is used when a TIN is in process. Check the box corresponding to 'Necesito una prórroga de un año para (Nombre del hijo adoptado) ATIN (ATIN asignado)' if this applies.
Form 15100 (sp) — what should I check?
Use it when requesting an extension of a Taxpayer Identification Number during the adoption process. Verify that your situation matches one of the listed circumstances on page 1.
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