KiwiSaver Medical Withdrawal Documents Checklist (2025 Guide)

If you’re applying for a KiwiSaver withdrawal to help fund weight loss surgery — such as gastric sleeve, gastric bypass or mini bypass — your application will only move quickly if your documentation is complete and well-organised.

In 2025, KiwiSaver providers are more strict about documentation, especially for medical and financial hardship withdrawals. Missing even one document can delay your application by weeks.

This guide provides the exact checklist of what you need for a successful application, including:

• Required documents (medical, financial, identity)

• Optional documents that strengthen your case

• Provider variations (Booster, Fisher Funds, Aurora, Milford, Simplicity, ANZ, AMP)

• Tips to avoid delays

• A downloadable-style checklist you can follow step-by-step

If you haven’t seen it yet, start with the full guide:
👉 KiwiSaver for Weight Loss Surgery (2025 Guide)

🟦 1. Mandatory Documents for All KiwiSaver Withdrawals

Regardless of provider, you will always need:

✔ 1. KiwiSaver Withdrawal Application Form

Download the version specific to your provider.

This form includes:

• your personal details

• purpose of withdrawal

• statutory declarations

• medical or hardship sections

• document checklist

Tip: Do not leave any section blank — incomplete forms cause automatic delays.

✔ 2. Proof of Identification

Usually one of the following:

• Passport

• Driver licence

• NZ birth certificate

• Citizenship certificate

Some providers may require certified copies.

✔ 3. Proof of Address

Any of:

• utility bill

• bank statement

• government letter

• rental agreement

Must show your name + address.

🟩 2. Medical Documentation (Essential for Bariatric Surgery)

KiwiSaver providers require evidence that surgery is medically necessary.

You will need:

✔ 4. GP Medical Letter (Required)

The most important document.

Must include:

• Diagnosis

• BMI + weight + height

• Comorbidities

• Treatment history

• Why surgery is recommended

• Why it should not be delayed

Use our template here:

👉 KiwiSaver GP Letter Template for 2025

✔ 5. Specialist Notes (If available)

Helpful but not mandatory.

Examples:

• Bariatric surgeon consultation notes

• Sleep study

• Endocrinology reports

• Diabetes metabolic reports

✔ 6. Medical History Summary (Optional but useful)

Often improves approval speed.

🟧 3. Surgery Documentation (Cost Evidence)

KiwiSaver providers require proof of the surgery's cost.

✔ 7. Formal Cost Estimate from Your Bariatric Clinic

Must include:

• Surgery type (sleeve, bypass, mini-bypass)

• Total cost (GST included)

• Hospital + anaesthesia fees

• Pre-op test fees

• Clinic details

✔ 8. Invoice or Booking Confirmation (If applicable)

Especially useful for medical-only withdrawals.

🟩 4. Financial Documentation (Required for Hardship Applications)

If you are applying under significant financial hardship, you will need additional documents.

✔ 9. Last 3 Months of Bank Statements

For all accounts, including:

• personal

• joint

• savings

• credit card accounts (sometimes requested)

Statements must show:

• income deposits

• rent/mortgage payments

• living costs

• recurring bills

✔ 10. Income & Expense Breakdown

Providers often require a budget summary showing:

• rent

• utilities

• food

• transport

• debt payments

• child-related costs

✔ 11. Debt or Overdue Notices (If relevant)

Examples:

• overdue bills

• loan arrears

• credit card overdue statements

✔ 12. Proof of Inability to Obtain Alternative Funding

May include:

• loan decline letters

• insurance exclusions

• savings account balances

• financial hardship letters

Some providers (e.g., Simplicity) ask for more detail.

🟫 5. Provider-Specific Requirements (2025 Updates)

⭐ Booster (Bariatric-friendly)

Typically requires:

• GP letter

• Cost estimate

• Bank statements (if hardship)

• ID + proof of address

Straightforward process.

⭐ Fisher Funds (Clear and structured)

Often requests:

• GP letter

• Detailed medical info

• Clear cost breakdown

• Full bank statements

Easy to work with if the documents are complete.

⭐ Aurora (Fast hardship decisions)

Requires:

• GP letter (if medically relevant)

• Bank statements

• Expense breakdown

Simple and fast, especially for hardship.

Milford

Strict about:

• financial documentation

• discretionary spending explanations

But good with medical withdrawals if GP letter is detailed.

Simplicity

The strictest provider for hardship.

Often requires:

• extended bank history

• very detailed budgets

• proof of loan declines

Be prepared for follow-up requests.

ANZ

Balanced and fair.

Requires:

• detailed GP letter

• cost estimate

• financial disclosure (if hardship)

AMP

Accepting but thorough.

Expect follow-up questions.

Requires:

• medical evidence

• financial summary

• income verification

🟪 6. Optional Documents That Strengthen Your Case

These are not required but significantly increase approval chances:

✔ Personal Statement

Explains why surgery is essential and unaffordable without KiwiSaver.

✔ Weight-related diagnostic reports

e.g., sleep apnea, HbA1c, blood pressure logs.

✔ GP referrals from previous years

Shows consistent medical need.

✔ Mental health impact letter

If weight affects mental wellbeing or quality of life.

🟦 7. Full Downloadable-Style Checklist

Here is the complete checklist in one place:

IDENTITY

• ID (passport or driver licence)

• Proof of address

MEDICAL

• GP letter (required)

• Specialist notes (optional)

• Medical history summary

• BMI + comorbidity documentation

SURGERY DOCUMENTS

• Formal cost estimate

• Invoice or booking confirmation

FINANCIAL (Hardship only)

• 3 months of bank statements

• Income & expense worksheet

• Debt or overdue notices

• Loan decline letters (if any)

• Proof of inability to self-fund

FORMS

• Provider-specific withdrawal form

• Statutory declaration (if required)

🟧 8. Common Documentation Mistakes

❌ Missing GP letter
❌ No cost estimate
❌ Missing bank accounts
❌ Inconsistent financial information
❌ Submitting photos instead of PDFs
❌ Sending documents in multiple emails
❌ Not explaining discretionary spending

Pro tip: Send everything in one single PDF to speed up processing.

🔗 Need the full process start to finish?

Read the complete guide here:
👉 KiwiSaver for Weight Loss Surgery (2025 Guide)

Not sure if you have everything ready?

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