Guides — start here

1) Figure jumped without explanation

1. Note the income figure, tax year/period, and shared-care band on the decision letter.
2. Run the estimate calculator with the same inputs and compare the CMS rate shown.
3. Request a written calculation breakdown (income source, other-child reduction, rate band).
4. If the input data is wrong, request mandatory reconsideration with evidence — usually within 30 days.

Open breakdown letter Open MR letter

2) Arrears I do not recognise

1. Build a payment ledger (bank statements + Direct Pay receipts) in the case timeline or My Case.
2. Request a full CMS arrears statement (line-by-line).
3. Use Arrears Audit — add payment lines, then export Excel for your pack.
4. Challenge unexplained items in writing; ask which payments were credited and which periods created the balance.

Opening arrears often appear when a case moves from Direct Pay to Collect & Pay. Ask CMS to show how those opening arrears were calculated — not only the current balance.

Open arrears audit Request arrears ledger

3) Enforcement has started

1. Record the enforcement type (wage deduction / DEO, deduction from benefits, court enforcement order, etc.), date, and amount.
2. Use the enforcement-review letter while a calculation or arrears dispute remains open.
3. Continue paying any undisputed amount where possible — say so in writing.
4. If affordability is the issue, ask what protected-earnings / deduction limits apply and request a written schedule.

Keep paying undisputed amounts. Stopping all payments can make the dispute harder even when part of the balance is wrong.

4) Decision challenge route (MR → tribunal)

1. Mandatory reconsideration within 30 days of the decision letter (late requests can sometimes be accepted — explain the delay).
2. Keep the mandatory reconsideration notice.
3. If still unhappy, appeal to the Social Security and Child Support Tribunal (form SSCS2), usually within one month of the MR notice.
4. Prepare a date list (timeline download) and a numbered evidence list before the hearing.

MR letter Tribunal cover note SSCS2 form (GOV.UK)

5) Service complaint route (complaint → ICE)

1. Raise a CMS/DWP service complaint for delays, missing explanations, or poor handling.
2. Ask for a complaint review if the first reply is inadequate.
3. After a final complaint response that refers you to ICE, escalate to the Independent Case Examiner — usually within 6 months (check your letter).
4. If needed later, your MP can help with a Parliamentary and Health Service Ombudsman (PHSO) referral.

Complaint letter ICE letter Find your MP

6) Shared care nights look wrong

1. List overnight dates from diaries, school calendars, court orders, or messages.
2. Check which overnight band CMS applied (52–103, 104–155, 156–174, 175+).
3. Run the calculator with the nights you can evidence, then request a correction in writing.
4. If CMS refuses, use mandatory reconsideration with the overnight schedule attached.

Shared care letter Calculator

7) Moved onto Collect & Pay / fee shock

1. Confirm whether you are on Direct Pay or Collect & Pay — fees only apply on Collect & Pay.
2. Paying parents are charged a 20% collection fee on top of maintenance; receiving parents 4% (GOV.UK).
3. Ask for a written schedule showing maintenance vs fees vs arrears recovery.
4. If Direct Pay payments were made but not recognised, rebuild the payment ledger before challenging fees or arrears.

Read the sourced overview on Findings → Collect & Pay fees.

8) Evidence checklist

Redact children’s full names and third-party details where possible. Store originals in My Case and export a pack when you escalate.