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Official form guide
Form 5305C: Health Savings Custodial Account
Internal Revenue Service Form 5305-C is a model custodial agreement that creates a Health Savings Account for the account owner and is signed by the owner and custodian. Contributions must be made before the tax‑return filing deadline (no extensions).
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IRS Form 5305C - Health Savings Custodial Account
Internal Revenue Service Form 5305-C is a model custodial agreement that creates a Health Savings Account for the account owner and is signed by the owner and custodian. Contributions must be made before the tax‑return filing deadline (no extensions).
Risk Radar
Scan points- 1Sending Form 5305-C to the IRS instead of keeping it with your records.
- 2Account owner’s signature line left blank or unsigned.
- 3Custodian’s signature line left blank or unsigned.
- 4Missing witness signature when a witnessed signature is required.
- 5Account owner’s date of birth not entered.
Plain English
Form 5305-C sets up a Health Savings Account between you and a custodian. You fill in your name, birth date, address, and the custodian’s business details, then both sign. The signed agreement is kept with your records, not mailed to the IRS.
Submission Date
- Filing date: 2017-02-08 00:00:00
- 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 establishing a Health Savings Account (HSA) as a custodial agreement between an account owner and a custodian.
- Do not use it when the account owner is enrolled in Medicare, is claimed as a dependent on another person’s tax return, or is covered by a non‑HDHP health plan.
- Check Not stated in the official source
Form selector
Use this form or another form?
Opening an HSA for a spouse who is also eligible
Each spouse must have a separate custodial agreement
✓ Verify spouse meets HDHP and Medicare criteria
Employer makes contributions on behalf of the employee
Contributions must be reported and limits observed
✓ Confirm employer’s contribution does not exceed family limit
Rolling over funds from an Archer MSA
Rollover must be completed within 60 days and limited to one per year
✓ Ensure rollover meets timing and frequency rules
Deadline or filing window
The agreement can be completed at any time during the tax year. Contributions to the HSA must be deposited before the account owner’s federal income tax return filing deadline for that year, and no extensions are permitted. There is no separate filing deadline for the form itself.
Checklist
What you need before filling it out
Name of account owner
Legal name of the individual · Form field 'Name of account owner'
Date of birth of account owner
Birth certificate or passport · Form field 'Date of birth of account owner'
Cash amount assigned to custodial account
Dollar amount to be deposited · Section stating '$ dollars in cash is assigned...'
Custodian’s signature
Authorized signature of custodian · Signature line for custodian
Witness signature (if required)
Witness name and signature · Witness signature line
Before you submit
- 1Verify account owner’s name is entered correctly.
- 2Enter account owner’s date of birth.
- 3Provide account owner’s street address, city, state, ZIP code.
- 4Indicate the cash amount assigned to the custodial account.
- 5Confirm eligibility criteria (HDHP coverage, no other non‑HDHP plan, not enrolled in Medicare, not a dependent) are met.
- 6Obtain custodian’s name and business address.
- 7Secure custodian’s signature and date.
- 8Include witness signature if the form requires it.
- 9Keep the completed Form 5305-C with personal records and do not mail to the IRS.
How to file this form
- 1Complete all required fields on Form 5305-C.
- 2Obtain the account owner’s signature and date.
- 3Obtain the custodian’s signature and date.
- 4Add a witness signature if the form indicates it is required.
- 5Retain the fully executed form in your records as proof of HSA establishment.
Known limitations
- 1Cannot be used by individuals enrolled in Medicare.
- 2Cannot be used by persons claimed as dependents on another taxpayer’s return.
- 3Cannot be used when the account owner is covered by a non‑HDHP health plan (except limited preventive coverage).
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->Form 5305-C is the October 2016 revision (Rev. October 2016). The source does not reference a newer version.
What changed or needs a fresh check
- Edition date — confirm the revision reads 10-2016 (Rev. October 2016) (Form p.1)
- Fee — Not stated in the official source
- Mailing address — Not stated in the official source
- Signature — confirm both account owner and custodian signatures are present (Form p.2)
- Witness signature — confirm witness signature is included only if required (Form p.2)
Quick Facts
Downloads
After you file
- 1Store the signed Form 5305-C with your HSA records.
- 2Retain the form for the life of the HSA (duration not specified in source).
- 3No confirmation will be sent by the IRS because the form is not filed.
- 4If an error is discovered, correct it by executing a new custodial agreement and keep both versions.
Sources
- SRCForm p.1 — revision date reads Rev. October 2016 (10-2016).
- SRCForm p.1 — purpose: model custodial account agreement approved by the IRS.
- SRCForm p.1 — eligibility criteria: covered under HDHP, not covered by other non‑HDHP plan, not enrolled in Medicare, not a dependent.
- SRCForm p.2 — instruction not to file with the IRS; keep with records.
- SRCForm p.2 — additional tax on non‑qualified distributions increased to 20% for tax years after 12/31/2010.
- SRCForm p.2 — disposition rules for death of account owner (spouse, estate, other beneficiaries).
- SRCForm p.2 — identification number is the account owner’s Social Security Number.
- SRCForm p.2 — EIN required for an HSA that files a return for unrelated business taxable income.
Common confusion points
Do I need to mail Form 5305-C to the IRS?
The form is a custodial agreement, not a tax return.
→ Verify the instruction 'Do not file Form 5305-C with the IRS' on page 2.
Can I use the same Form 5305-C for both spouses?
Each spouse must have a separate account.
→ Check the statement that each spouse must establish his or her own account.
What is the maximum contribution amount?
The form does not list dollar limits; they are set by law.
→ Refer to current IRS contribution limits for HSAs (not in this form).
Is a witness always required?
Witness signature is optional, only if required by the parties.
→ Confirm whether a witness line is filled before filing.
Will the IRS tax my HSA if I die?
Disposition rules depend on beneficiary type.
→ Review Article VII on page 2 for beneficiary treatment.
Do I need an EIN for my HSA?
EIN is required only for HSAs that file a return for unrelated business income.
→ Check the definition section for EIN requirement.
Workflow map
Related forms and next steps
Before
Current
After
Often used with
⚠ If something goes wrong
- Form 5305-C — amend or terminate the agreement per additional provisions.
Questions about IRS Form 5305C
What is IRS Form 5305C used for?
Form 5305-C sets up a Health Savings Account between you and a custodian. You fill in your name, birth date, address, and the custodian’s business details, then both sign. The signed agreement is kept with your records, not mailed to the IRS.
Who must file IRS Form 5305C?
The account owner and the custodian must complete and sign IRS Form 5305-C.
What information does IRS Form 5305C require?
The form collects the account owner’s name, date of birth, address, and Social Security number, as well as the custodian’s name and principal business address, and requires signatures of both parties.
Where do I file IRS Form 5305C?
Do not file Form 5305-C with the IRS; keep the executed agreement with your personal records.
How do I complete IRS Form 5305C?
Enter the account owner’s personal information on the first section, then list the custodian’s name and principal place of business. Both parties sign the designated lines, and a witness signs only if required. The custodian agrees to file any required IRS reports. After signatures, retain the completed form in your records.
What happens if IRS Form 5305C is filed incorrectly?
If contributions exceed the annual limit, the excess is subject to an excise tax, and non‑qualified distributions may trigger a 20% additional tax.
Do I need to mail Form 5305-C to the IRS?
The form is a custodial agreement, not a tax return. Verify the instruction 'Do not file Form 5305-C with the IRS' on page 2.
Can I use the same Form 5305-C for both spouses?
Each spouse must have a separate account. Check the statement that each spouse must establish his or her own account.
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