Section 4.55 Modification Applications in NSW 2026: Complete Guide to the March Reform Changes, Pathways & Fees

How do you modify an existing development consent in NSW?

You modify an existing development consent in NSW by lodging a section 4.55 modification application with the original consent authority through the NSW Planning Portal. Section 4.55 of the Environmental Planning and Assessment Act 1979 (EP&A Act) provides three statutory pathways — 4.55(1), 4.55(1A), and 4.55(2) — each determined by the environmental impact of the proposed change. Since 21 March 2026, the rules have been materially reshaped by the Environmental Planning and Assessment Amendment (Planning System Reforms) Act 2025, introducing a 14-day deemed approval pathway for no-impact modifications and expanding the scope of what qualifies for the fast lane.

For developers, homeowners, and builders in NSW, understanding these three pathways is the difference between a two-week administrative process and a six-month full reassessment that can break a project’s feasibility. The reform changes are not retrospective — they apply to any modification application lodged on or after 21 March 2026, regardless of when the original DA was approved.

What changed in the March 2026 planning reforms?

The second tranche of the Environmental Planning and Assessment Amendment (Planning System Reforms) Act 2025 commenced on 21 March 2026, introducing the most significant changes to section 4.55 in decades. The NSW Department of Planning, Housing and Infrastructure confirmed that these changes apply to all modification applications lodged from that date forward, meaning a developer with a consent granted years ago is assessed under the new framework, not the one that existed when the original approval was issued.

The most consequential change is the expansion of section 4.55(1). Under the old rules, this pathway was confined to correcting minor errors, misdescriptions, and miscalculations — typographical mistakes, incorrect plan references, or arithmetic errors in conditions. It was almost useless for genuine design changes. The new section 4.55(1) also captures any modification that the consent authority is satisfied will have no environmental impact, and it now carries a 14-day deemed non-refusal clock under the new section 4.55A. If the council does not determine the application within 14 days of lodgement, it must do so as soon as practicable afterwards and must not refuse it.

A second key change is the introduction of section 4.55(1A) as a distinct pathway for modifications with minimal environmental impact. Previously, the old section 4.55(1) covered both minor errors and minimal-impact changes in a single provision. The reforms split these into two tiers, creating a clearer progression: no impact (4.55(1)), minimal impact (4.55(1A)), and more than minimal impact (4.55(2)).

The reforms also expanded the review and appeal rights. Applicants now have up to six months to request a review of a modification decision, with the appeal clock paused while a review is on foot. The deemed refusal appeal pathway has been broadened so that an appeal can be lodged at any time before the application is determined, rather than only after a fixed waiting period has elapsed.

What are the three section 4.55 modification pathways?

The three pathways are structured as a tiered system, where the pathway is determined by the environmental impact of the change, not by how large the change appears on paper. A developer who understands which tier a proposed change sits in can predict the fee, the notification requirement, the assessment timeframe, and the likelihood of objection before lodging anything.

Section 4.55(1): Minor error or no environmental impact (the fast lane)

Section 4.55(1) is the streamlined pathway, and the 2026 reforms widened it considerably. It now covers two categories of change. The first is the traditional one: correcting a minor error, misdescription, or miscalculation — a typographical mistake, an incorrect reference to a plan or document, or an arithmetic or drafting error in a condition. The second, and the genuinely new category, is any modification that the consent authority is satisfied will have no environmental impact.

The Department’s practice note is precise about what “no environmental impact” means. It is a threshold test, not a balancing exercise. The modification must not introduce any new negative environmental impact, including any increase to the severity or distribution of an existing impact. If a change reduces impact in one respect but shifts or introduces impact in another, it fails the threshold even though it might be an improvement overall. The consent authority is directed to consider whether any element of the environment could be affected — amenity, air quality, biodiversity, Aboriginal cultural heritage, water, soils, environmental heritage, and economic and social factors.

The reward for fitting within section 4.55(1) is speed. Applications do not require notification, the maximum fee is the lowest of any pathway at approximately $95 for the 2025-26 financial year, and the 14-day deemed non-refusal clock provides a strong statutory tailwind. The council cannot sit on the application indefinitely, and it cannot use the modification as an opening to reopen settled parts of the consent.

One carve-out applies: the deemed non-refusal framework does not apply to an application seeking to modify a housing and productivity contribution condition imposed under section 7.28, unless the Minister has approved the proposed modification under section 7.28(6).

Section 4.55(1A): Minimal environmental impact

Section 4.55(1A) is for modifications that do involve some change to environmental impact, but only where that impact remains minimal. The Department’s practice note reads “minimal” in its ordinary sense of very small or negligible. Two separate requirements must be satisfied: the consent authority must be satisfied that the modification would result in only minimal environmental impact, and it must be satisfied that the development as modified would be the same or substantially the same as the development originally approved.

Because section 4.55(1A) involves a change to environmental impact, notification may be required, and the application is assessed on its merits rather than being subject to the 14-day deemed non-refusal clock. Typical changes include internal reconfigurations, amended landscape plans, drainage design amendments, and minor external changes that do not materially affect privacy, height, overshadowing, or streetscape. The maximum fee is the lesser of approximately $859 (in 2025-26 terms) or 50 per cent of the fee that was paid for the original application.

Section 4.55(2): Other modifications

Section 4.55(2) is the catch-all for changes that cannot be dealt with under 4.55(1) or 4.55(1A). It covers modifications that would result in more than no or minimal environmental impact, but where the development as modified would still be the same or substantially the same as the development originally approved. This is the pathway for substantive design changes: altered building heights within the envelope, changed floor levels, reconfigured car parking, a different roof form, additional dwellings, or a revised unit mix.

Section 4.55(2) applications are assessed broadly like a scaled-down DA. They generally require notification, are open to submissions, and are assessed on their merits against the relevant matters. The fee is scaled by the estimated cost of the works the modification relates to, and where notification is required, an additional notification fee applies.

Section 4.55 Pathway Comparison Table

How much does a section 4.55 modification cost?

Modification fees in NSW are set as maximum fees under Schedule 4, Part 4 of the Environmental Planning and Assessment Regulation 2021, expressed in fee units. The fee unit for 2025-26 is $113.90 and is indexed each 1 July. A council may charge less than the maximum, but not more.

For a practical example, consider a section 4.55(2) modification to an approved apartment building where the works the modification relates to have an estimated cost of $3 million. Under the scaled fee for works between $1 million and $10 million, the base fee is 11.54 fee units (approximately $1,314) plus $0.40 for each $1,000 by which the cost exceeds $1 million, adding approximately $800 on a $3 million figure, for a base of roughly $2,114. If the modification must be notified, add the notice fee of approximately $886, plus the portal lodgement fee of approximately $46. The total council fees come to approximately $3,000, before consultant and design costs.

For state significant development, the fees are higher: a section 4.55(1) modification attracts approximately $1,132, and a section 4.55(1A) modification approximately $6,660, reflecting the larger scale of those projects.

Modification Fee Schedule (2025-26 Financial Year)

What is the “same or substantially the same development” test?

The “substantially the same” requirement is the gate that controls both section 4.55(1A) and 4.55(2). If a proposed modification cannot be characterised as resulting in a development that is the same or substantially the same as the one originally approved, it cannot proceed as a modification at all, and the developer must lodge a fresh DA.

The Department’s practice note frames the test cleanly: “substantially” means “essentially or materially having the same essence.” The onus sits on the applicant to demonstrate that the modified development is the same or substantially the same. Crucially, the comparison is between the development as originally approved and the development as proposed to be modified — not against the development as previously modified, and not against what has actually been built on site.

The leading authority is Moto Projects (No 2) Pty Ltd v North Sydney Council [1999] NSWLEC 280, which established that the comparison should weigh quantitative differences (changes to height, gross floor area, setbacks), qualitative differences (changes to land use, configuration, amenity), the material and essential features of the two developments, and the consequences of carrying them out.

This approach was recalibrated by the Land and Environment Court in 2024. In Realize Architecture Pty Ltd v Canterbury-Bankstown Council [2023] NSWLEC 1437, the Court approved a modification to a large mixed-use development that added two storeys on top of an originally approved nine-storey building and an additional 2,368 square metres of gross floor area (approximately 9.8 per cent increase), along with ten additional dwellings and a complete reconfiguration of the car park and communal open space. The Chief Judge endorsed a “balanced” three-step approach: identify the primary facts, interpret the statutory words, and categorise the facts through an evaluative exercise. Large numerical changes do not automatically fail the test; what matters is the nature, extent, and effect of the differences taken as a whole.

When should you modify vs lodge a fresh DA?

The decision to modify or lodge a fresh Development Application is the most consequential strategic call in the process. A modification keeps the existing consent alive, narrows the assessment to the change itself, attracts a smaller fee, and generally runs faster. A fresh DA reopens the entire scheme to assessment, exposes it to current planning controls (which may have tightened since the original consent), restarts notification and submissions, and resets the programme clock by six to twelve months.

The key question is whether the change involves “alteration without radical transformation.” If what is proposed would radically transform the approved development, it is not a modification, and a fresh DA is required regardless of how the application is framed. Examples of changes that typically require a fresh DA include changing the land use entirely, increasing the number of storeys beyond what the planning controls allow, or redesigning the development so substantially that it bears no resemblance to the original approval.

In our experience at giantA, the modify-versus-fresh-DA decision is a commercial call before it is a legal one. We have seen projects in Parramatta and Western Sydney where a well-argued modification saved clients 14 weeks of re-assessment time and avoided the risk of the development being judged against tightened planning controls. The cost of a planning consultant to make the strongest possible “substantially the same” case is almost always less than the cost of being wrong and starting again.

What documentation do you need for a section 4.55 application?

All section 4.55 modification applications must be submitted via the NSW Planning Portal. The documentation required varies by pathway but generally includes:

For a section 4.55(1) application, you need updated plans that clearly illustrate the proposed modifications, a statement identifying the specific changes being sought, and confirmation that the modification will have no environmental impact. Because there is no notification requirement, the documentation can be lean.

For section 4.55(1A) and 4.55(2) applications, the requirements are more substantial. You need a Statement of Environmental Effects (SOEE) specific to the modification that addresses the environmental impact of the change, updated plans showing the approved development and the proposed modification side by side, any necessary technical or specialist reports (such as updated traffic, acoustic, or heritage assessments), and evidence that the modified development is the same or substantially the same as the original.

The SOEE is a critical component. It should clearly identify what is changing, explain why the change is needed, assess the environmental impact of the change, and demonstrate how the modified development remains substantially the same. A poorly prepared SOEE is one of the most common reasons for modification applications being refused or delayed.

What are the common reasons modifications get refused?

Modifications get refused for a recurring set of reasons, and knowing them in advance is the cheapest form of risk management. In our practice at giantA, we see the same patterns repeat across councils in Parramatta, Cumberland, Blacktown, and Fairfield.

The first and most fundamental is failing the “substantially the same” test. A change that goes beyond alteration into radical transformation cannot be a modification. The way to manage this is to test the change against the original approval before lodging, and where the call is marginal, to build a holistic comparison — side-by-side elevations, three-dimensional comparisons, a macro rather than micro reading of the scheme.

The second is pushing a change into a pathway it does not fit. A modification with real environmental consequences lodged as a no-impact section 4.55(1) application will be bumped to the correct pathway after the council’s early categorisation check, costing time and sometimes a re-lodgement fee. The Department’s guidance tells councils to check within seven days of submission whether an application has been put in the right pathway. Categorise honestly and lodge in the right tier the first time.

The third is incomplete information. Because the comparison is against the original approval, a modification application that does not clearly identify what is changing, or that does not give the council the material it needs to be satisfied on impact, invites refusal or a request for more information that stops the clock. The fourth is using a modification to regularise unauthorised work already carried out on site — this is possible in principle but is assessed carefully, and a poorly prepared application of this kind is a common refusal.

How long does a section 4.55 modification take?

The timeframe depends on the pathway. A section 4.55(1) application carries the 14-day deemed non-refusal clock under section 4.55A, making it the fastest modification pathway in NSW planning history. In practice, a well-prepared 4.55(1) application can be determined within two to three weeks of lodgement.

Section 4.55(1A) and 4.55(2) applications are assessed on their merits and are subject to a deemed refusal period, after which an applicant dissatisfied with the delay can treat the application as refused and appeal to the Land and Environment Court. In our experience, 4.55(1A) applications typically take four to eight weeks, while 4.55(2) applications can take eight to sixteen weeks depending on whether notification is required and whether submissions are received.

The 2026 reforms expanded the deemed refusal appeal rights so that an appeal can be lodged at any time before the application is determined, rather than only after a fixed waiting period has elapsed. This gives developers more flexibility about when to escalate a stalled modification. The Land and Environment Court’s Class 1 jurisdiction hears these appeals, and they are determined afresh on the merits.

What about consents granted by the Land and Environment Court?

Section 4.55 applies to consents granted by a consent authority — typically a council, a local or regional planning panel, or the Independent Planning Commission. Where a consent was instead granted by the Land and Environment Court on a development appeal, the modification is dealt with under section 4.56 of the EP&A Act, which allows a consent authority to modify a Court-granted consent on substantially the same principles, including the “substantially the same development” test. The fee items in Schedule 4 mirror this, applying the same fees to section 4.56 applications as to their section 4.55 equivalents.

If a developer is dissatisfied with how a council determines a modification, the right of appeal is found in section 8.9 of the EP&A Act, which allows an appeal to the Land and Environment Court against a refusal or against a modification granted on terms the applicant is unhappy with. The appeal must generally be brought within six months, and the fee is 50 per cent of the fee that was payable for the modification application itself.

How does this affect homeowners versus developers?

The impact of the March 2026 reforms varies significantly depending on who you are and what you are trying to achieve.

For homeowners with an approved DA for a new dwelling or renovation, the expanded section 4.55(1) pathway is good news. Common homeowner modifications — swapping a material finish, adjusting a window placement that does not affect overshadowing, correcting a plan error — can now be processed in 14 days without notification, saving weeks of waiting and hundreds of dollars in fees. The key is understanding that “no environmental impact” is a strict threshold, not a matter of degree.

For developers running multi-unit projects, the reforms create a strategic decision point. The 14-day deemed approval for 4.55(1) applications is a genuine fast lane, but it places pressure on getting the categorisation right. Lodging an ambitious change as a 4.55(1) to chase the 14-day clock, when it plainly carries some impact, tends to cost time rather than save it. The expanded appeal rights give developers more leverage when councils stall, but the proportionate assessment principle in section 4.55(3) — which limits the council to assessing only the matters relevant to the modification — is the provision that developers should invoke most often when a council tries to reopen settled parts of a consent.

For builders and certifiers, the reforms mean that condition-only modifications (such as varying an unworkable construction-hours condition or adjusting the timing of a contribution) are explicitly confirmed as valid under section 4.55(5). This resolves a previous grey area where some councils argued that a modification required a physical change to the approved development. The documentation requirements remain the same, but the pathway is now clearer.

What should you do before lodging a modification application?

Before lodging any section 4.55 application, we recommend a structured pre-lodgement review that covers five steps. First, characterise the change against the original approval, not against what has been built or last modified. Ask whether it is alteration or radical transformation. Second, assess the environmental impact honestly — if any element of the environment could be affected, the change does not qualify for 4.55(1). Third, prepare the comparison material that demonstrates the development remains substantially the same, using side-by-side plans and a clear SOEE. Fourth, confirm you have standing to lodge — only the original applicant, the current landowner, or a person with the owner’s authority can apply. Fifth, run the numbers: the modification fee is usually the small cost; the real cost is the time it takes and any change it forces in yield, contributions, or holding costs.

At giantA, we have helped clients across Western Sydney and the broader Sydney metropolitan area navigate modification applications for residential, duplex, and multi-unit developments. Our team can assess your proposed change, identify the correct pathway, prepare the SOEE and comparison material, and lodge the application through the NSW Planning Portal. If you are considering a modification to an existing consent, contact us for an initial assessment.

FAQ: Section 4.55 Modification Applications

Can I modify my development consent without a new DA?

Yes, if the proposed change results in a development that is the same or substantially the same as the originally approved development and does not radically transform it, you can lodge a section 4.55 modification application. The pathway depends on the environmental impact: no impact goes through 4.55(1) with a 14-day clock, minimal impact through 4.55(1A), and more substantial changes through 4.55(2). If the change radically transforms the development, a fresh DA is required.

How long does a section 4.55(1) modification take in NSW?

A section 4.55(1) modification application must be determined within 14 days of lodgement under the new section 4.55A deemed non-refusal framework, which commenced on 21 March 2026. If the council does not determine it within 14 days, it must do so as soon as practicable afterwards and must not refuse it. In practice, a well-prepared application with all documentation complete can be approved within two to three weeks.

What is the fee for a section 4.55 modification in NSW?

The maximum fee for a section 4.55(1) modification is approximately $95 for the 2025-26 financial year. For 4.55(1A), the maximum is the lesser of approximately $859 or 50 per cent of the original application fee. For 4.55(2), the fee is scaled by the estimated cost of the works, plus an additional notification fee of approximately $886 if notification is required. Fees are indexed annually on 1 July.

What happens if my modification has environmental impact?

If your modification has any environmental impact, it cannot proceed under section 4.55(1) and must be lodged under 4.55(1A) for minimal impact or 4.55(2) for more substantial impact. These pathways require merit assessment, may require notification, and do not benefit from the 14-day deemed approval clock. The consent authority will assess the modification against the relevant matters in section 4.15(1) of the EP&A Act, but only to the extent relevant to the proposed change.

Can I appeal a council refusal of my modification application?

For section 4.55(1) applications, there is no right of appeal on the determination. For 4.55(1A) and 4.55(2) applications, you can appeal a refusal to the Land and Environment Court under section 8.9 of the EP&A Act within six months. You can also request an internal review of the decision within six months, with the appeal clock paused while the review is on foot. The 2026 reforms expanded these rights so appeals can be lodged at any time before determination if the application is stalled.

Do the March 2026 reform changes apply to my old development consent?

Yes. The reform changes apply to any modification application lodged on or after 21 March 2026, regardless of when the original DA was approved. A developer with a consent granted ten years ago who lodges a modification today is assessed under the new framework. The date that matters is the date the modification is lodged, not the date the consent was issued. Modifications lodged before 21 March 2026 are assessed under the old framework.

What is the difference between section 4.55 and section 4.56?

Section 4.55 applies to modifications of consents granted by a consent authority (council, planning panel, or the Independent Planning Commission). Section 4.56 applies to modifications of consents granted by the Land and Environment Court on a development appeal. The principles are substantially the same, including the “substantially the same development” test, and the fee schedule mirrors the section 4.55 fees. If your consent was granted on appeal, you use section 4.56.

Author: Franz Phan, Senior Planning Consultant, giantA Pty Ltd. Franz has 15+ years of experience in NSW development approvals, modification applications, and multi-unit residential design across Western Sydney and the broader Sydney metropolitan area.

Sources: Environmental Planning and Assessment Act 1979 (NSW); Environmental Planning and Assessment Amendment (Planning System Reforms) Act 2025; Environmental Planning and Assessment Regulation 2021 (Schedule 4); NSW Department of Planning, Housing and Infrastructure practice note on section 4.55 modifications (March 2026); NSW Planning Portal 20 March 2026 release summary; Bartier Perry, “NSW planning reforms bring deemed approval, tighter deadlines and increased pressure” (24 June 2026); Feasly, “Section 4.55 Modifications NSW: A Developer’s Guide”; Moto Projects (No 2) Pty Ltd v North Sydney Council [1999] NSWLEC 280; Realize Architecture Pty Ltd v Canterbury-Bankstown Council [2023] NSWLEC 1437; Canterbury-Bankstown Council v Realize Architecture Pty Ltd [2024] NSWLEC 31.