CCSD code C3113 – Bilateral squint surgery

Key takeaways

CCSD Code C3113 applies only when squint surgery is performed on both eyes in the same operative episode, distinguishing it from C3112 (unilateral).

All major UK PMIs require prior authorisation before bilateral squint surgery. A late or missing pre-auth is the most common reason these claims are denied.

Pair C3113 with the clinically accurate ICD-10 H50 diagnosis code. The operative note must record each muscle operated on and the technique used.

Pabau’s private practice billing tools support CCSD code-based invoicing and structured operative documentation to reduce claim errors.

What is CCSD Code C3113 and what does it cover?

CCSD Code C3113 is the procedure code for surgical correction of squint (bilateral), used across UK private medical insurance (PMI) billing. The Clinical Coding and Schedule Development Group maintains it. The code sits in Chapter 4 of the CCSD schedule, Eye and orbital contents, under section 4.4 (Muscles).

Its official descriptor is “Surgical correction of squint – bilateral.” It applies when a consultant ophthalmologist operates on the extraocular muscles of both eyes in one session.

Strabismus, commonly called a squint, is a misalignment of the eyes caused by imbalance in the extraocular muscles. Heterotropia, esotropia, exotropia, and hypertropia are all clinical presentations that may warrant surgical correction. When surgery is needed on both eyes in the same session, the procedure is coded C3113 rather than C3112.

The procedure: What bilateral squint correction involves

Bilateral squint correction targets the extraocular muscles of both eyes to achieve ocular alignment. The operating ophthalmologist may weaken a muscle by recession, strengthen one by resection, or combine both techniques.

• Muscle recession: the medial or lateral rectus is detached and reattached further from the cornea, reducing its mechanical force.
• Muscle resection: a segment of the muscle is excised to shorten it, increasing its pull.
• Adjustable sutures: sutures are left temporarily adjustable so alignment can be fine-tuned postoperatively under topical anaesthesia, typically on the same day.
• Bilateral scope: at least one muscle on each eye is operated on; in many cases, two or more muscles are involved across the two eyes.

General anaesthesia is standard for paediatric patients. Adult bilateral cases may be performed under local anaesthesia combined with sedation, though general anaesthesia remains common. The bilateral nature extends both operating time and recovery, which is why C3113 carries a higher fee weighting than C3112.

C3113 vs C3112: Bilateral vs unilateral squint surgery

What happened in theatre decides between C3113 (bilateral) and C3112 (unilateral). Submitting C3113 when only one eye was operated on constitutes miscoding and may be treated as fraudulent billing by insurers. The operative note must clearly confirm that muscles on both eyes were addressed.

C3113 vs C3180: Primary surgery vs revision of squint

A separate and frequently confused code is C3180, which covers revision of squint surgery. Submitting C3113 for a procedure that is clinically a revision will trigger a denial. The operative note and referral letter must make the primary-versus-revision status explicit.

Neighbouring CCSD codes in Chapter 4 (eye and orbital contents)

Chapter 4 of the CCSD schedule covers ophthalmic procedures, and squint surgery sits in its Muscles section (4.4). Coders selecting C3113 should know the adjacent codes to avoid misassignment. Our CCSD code index lists the rest of the schedule.

Before a C3113 claim leaves the practice, confirm that no other code from the same family fits better. Misassignment between adjacent codes is one of the leading causes of delayed payment in ophthalmic billing. Two questions settle it, in the order shown below.

Documentation requirements for CCSD Code C3113 claims

A complete claim file for C3113 needs the following components in place before submission. Missing any one of these is grounds for an insurer to suspend or deny the claim.

• Operative note: must name each muscle operated on and the eye it belongs to, plus the technique used (recession, resection, or adjustable suture). It must also state that both eyes were treated in the same operative session. A generic “bilateral squint surgery performed” entry without muscle-level detail will not satisfy most insurer audit requirements.
• Referral letter: confirms the GP or optometrist referral pathway and the consultant ophthalmologist’s name.
• Pre-authorisation confirmation: written authorisation from the insurer, with the authorisation reference number included on the invoice.
• Diagnosis coding: the correct ICD-10 H50 code matching the documented type of strabismus (see the table below).
• Invoice: itemised with C3113, the date of procedure, the consultant’s name, and the hospital or private facility.

A structured operative note template keeps every entry aligned to what insurers audit. Templates that capture muscle-level detail are far harder to deny than free-text operative summaries.

ICD-10 diagnosis codes to pair with C3113

Select the most specific H50 code that matches the documented clinical presentation. Broad or inaccurate pairings increase medical necessity denial risk.

Avoid submitting H50.9 (unspecified strabismus) alongside C3113. Insurers may interpret the combination as insufficient clinical specificity and pend the claim for additional records.

Prior authorisation: What UK insurers require before C3113

All major UK private medical insurers require prior authorisation before bilateral squint surgery. Submitting a C3113 claim without an authorisation reference number is the most common reason claims are rejected at the gateway.

Consult the Bupa CCSD billing guide for Bupa-specific submission requirements, and use each insurer’s portal for up-to-date pre-auth pathways.

Policy-specific requirements change annually. Always verify current pre-authorisation pathways directly with the insurer before the procedure date. Billing teams working with several PMI payers need one place to track authorisation status per patient.

Fee schedule guidance for C3113

CCSD fee schedules are negotiated individually by insurers and updated periodically. Specific fee amounts are not published universally, and any figure cited here would risk being out of date by the time a claim is submitted. The key principles that apply to C3113 fee claims across major PMIs are consistent, however.

• Bilateral premium: C3113 is reimbursed at a higher rate than C3112 because the bilateral procedure involves greater surgical complexity and longer anaesthesia. The Exeter’s published fee schedule and the Healix fee schedule both reflect this differential.
• Consultant fee vs facility fee: the consultant ophthalmologist’s C3113 fee is separate from the theatre, anaesthetist, and overnight facility charges. Each must appear on a distinct invoice line.
• Adjustable suture surcharge: some insurers may allow an additional code for the adjustable suture adjustment element. This is insurer-specific and must be confirmed in the pre-authorisation documentation before billing it; it is not universally accepted as a separate billable item.
• Bupa procedure codes fee schedule: Bupa-recognised consultants can check the current surgical fee category for Chapter 4 procedures in the Bupa procedure codes fee schedule. Bupa’s February 2026 schedule places C3113 in fee category MAJOR 3.

Which ancillary codes can be billed alongside C3113?

Anaesthetist, facility, orthoptic assessment and follow-up review fees can usually be billed separately, while adjustable suture adjustment depends on the insurer. Insurers apply bundling rules to ophthalmology claims. Codes considered inherent to the primary procedure lead to partial payment or rejection of those line items.

Common reasons C3113 claims are denied

Denial patterns for CCSD Code C3113 are predictable. Addressing these before submission saves significant administrative time and protects cash flow.

• Missing prior authorisation: submitting without an authorisation number, or submitting after the pre-auth has expired, results in automatic rejection at most insurers.
• Unilateral procedure billed as bilateral: if the operative note documents one eye only, the insurer will downcode the claim to C3112 or reject it.
• Inadequate operative note: a note that leaves out which muscles were treated on which eye, or omits the technique, lets an insurer request more records. Payment is suspended until they arrive.
• Wrong diagnosis code pairing: using H50.9 (unspecified) or a code that does not match the documented deviation type raises a medical necessity flag.
• Revision coded as primary: if the patient has had squint surgery before, an insurer audit will flag a C3113 claim that should have been C3180.
• Late submission: most PMIs impose a submission window (commonly 6 months from the procedure date). Claims submitted outside this window are rejected on timeliness grounds alone.
• Adult coverage restrictions: some insurers exclude adult-onset strabismus surgery or ask for extra medical necessity documentation for adults. This varies by insurer and policy, so confirm it before booking.

Adult vs paediatric strabismus: Does it affect C3113 eligibility?

No. The CCSD Code C3113 descriptor does not distinguish between adult and paediatric patients. The code applies to bilateral squint correction regardless of patient age. However, some UK PMI policies apply coverage restrictions or enhanced documentation requirements for adult-onset strabismus surgery that do not apply to childhood squint.

Paediatric cases are generally well-covered where the diagnosis is clear and prior authorisation is in place. Adult bilateral squint surgery, particularly where the squint is cosmetically driven rather than functionally disabling, may face additional scrutiny.

Some insurers may require evidence that conservative management (prism therapy, orthoptic exercises) has been trialled before approving surgical intervention in adults. This is a policy-level restriction, not a coding restriction, and it varies by insurer and individual policy year.

Billing teams supporting adult ophthalmology patients opting for private treatment, including those affected by NHS waiting times, should confirm coverage status at the pre-authorisation stage.

How to submit a C3113 claim: Step-by-step

A clean C3113 claim follows a consistent workflow from referral to payment. Missing steps at the front end (pre-auth, documentation) cause the most delays.

1. Receive the referral: confirm the patient’s PMI policy, membership number, and insurer. Record the referring clinician’s name and GMC number.
2. Request prior authorisation: before the procedure date, send the insurer the planned procedure (C3113), the consultant’s details, the proposed diagnosis code, and clinical evidence. Record the authorisation reference number.
3. Complete the operative note: document each muscle operated on, the technique used (recession, resection, adjustable suture), the eye (left/right), and confirm bilateral scope.
4. Assign codes: assign C3113 as the primary CCSD procedure code. Pair with the correct ICD-10 H50 diagnosis code. Confirm that C3180 is not the appropriate code before proceeding.
5. Raise the invoice: itemise C3113 with the date, procedure description, consultant name, facility, and the pre-authorisation number.
6. Submit through Healthcode or the insurer portal: most UK PMIs accept electronic submission via Healthcode. Some insurers accept direct portal submission. Attach the operative note if required by the insurer.
7. Track the claim and follow up: monitor payment status within the insurer’s stated processing window (typically 28 days). If payment is delayed, request the claim status in writing and reference the authorisation number.

Practices handling a high volume of CCSD claims get paid faster with automated claims management. It tracks each submission and flags outstanding authorisations before the procedure date.

How Pabau keeps C3113 claims clean from referral to payment

Many C3113 claims are assembled from three places. The operative note sits in a word-processed file, the pre-auth number in an email thread, and the invoice in a separate billing tool. Each hand-off is another chance for the muscle detail or the authorisation reference to fall off the claim.

Pabau, the practice management platform we build, keeps those pieces in one patient record. Its form builder turns your operative note into a structured template, so each muscle, eye and technique is captured on the day of surgery. The invoice is then raised from the same record.

Claim status sits next to the record too. Your team can see which bilateral squint claims are paid, pending or overdue without phoning each insurer.

Simplify CCSD billing for your ophthalmology practice

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Conclusion

A C3113 claim succeeds or stalls on its paperwork. The note has to prove three facts: both eyes, one session, and a first operation. Write the operative note and log the pre-auth reference before the invoice goes out, rather than rebuilding them after an insurer query.

For adult patients, settle policy exclusions at the pre-auth stage. Finding one after surgery turns an insured case into a self-pay conversation the patient did not plan for.

Templated notes and per-patient authorisation tracking mean fewer resubmissions and faster payment. Book a demo to see how Pabau builds each C3113 claim from the patient record.

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