The short answer
Interior designers in Philadelphia charge $57 to $520 an hour, and a single room runs $520 to $1,700 for design alone. None of the three states in this metro licenses interior designers. Pennsylvania and New Jersey protect a certification title, so ask what a designer holds.
What interior designers cost in Philadelphia
The ranges below apply the Philadelphia construction cost factor of 1.15 from the U.S. Army Corps of Engineers to national design fee data. They cover design work only. Furniture is separate.
| Job | Philadelphia (typical range) | US average |
|---|---|---|
| Interior designer, per hour | $57–$520/hr | $50–$450/hr |
| In-home consultation | $57–$520 | $50–$450 |
| One room, design only | $520–$1,700 | $450–$1,500 |
| One room, design and furnishing | $1,150–$13,800 | $1,000–$12,000 |
| Whole home, per sq ft | $6–$19.5/sq ft | $5–$17/sq ft |
| Whole home, 2,000 sq ft | $11,500–$39,100 | $10,000–$34,000 |
Estimates for 2026, including labor and standard parts. Philadelphia prices use the metro's construction cost factor of 1.15 (US average = 1.00) from the U.S. Army Corps of Engineers Area Cost Factors. Your quote depends on access, materials and the condition of the home.
Where you land in those ranges depends on the size of the job, the designer's experience, and how much buying the firm does for you. A principal bills near the top of the hourly range, a junior designer near the bottom. A whole-home job is usually priced by the square foot, a single room flat.
How Philadelphia designers bill
Most firms pick one fee structure. Some combine two on the same project, such as hourly for the concept and cost plus for the furniture.
| Fee structure | How it works | Watch for |
|---|---|---|
| Hourly | Time logged and billed at the designer's rate | Ask for a written estimate of hours |
| Flat fee per room | A fixed price for a defined scope | Get the scope in writing, including revision rounds |
| Per square foot | Common on whole-home and large remodel work | Confirm whether it covers furnishings or design only |
| Percentage of construction cost | Design priced as a share of the build | Ties the fee to the contractor's number |
| Cost plus | The designer buys and adds a percentage | Ask for the net price on every invoice |
| Markup on retail | A percentage added to the retail price | Ask whether markup is calculated before or after tax |
Charges that surprise people
A retainer is normally due at signing, and some firms ask for a large share of the project up front. Product deposits can run to half the cost of the furniture the firm orders for you. A designer who manages trades during construction usually adds a management fee on top of the design fee. Travel time is often billed at a reduced hourly rate, which matters when the designer drives from Center City to a job in Bucks County. Drawings are sometimes billed separately from design time.
Sales tax on furnishings
Tax depends on where the goods are delivered. In Philadelphia the combined rate is 8%: 6% Pennsylvania sales tax and 2% Philadelphia tax. From October 1, 2026 the city's 2% share is collected based on the delivery address, not the seller's location, so an out-of-city business shipping to a Philadelphia address must collect it. In New Jersey the rate is 6.625%, and if you paid less tax in another state on an item delivered to New Jersey, you owe Use Tax on the difference. On a large furnishing budget, the gap between the two rates adds up. Ask the designer whether tax appears as its own line and whether markup is calculated before or after it.
Does a designer need a license in Pennsylvania, New Jersey or Delaware?
No. None of the three states requires a license to practice interior design. Pennsylvania and New Jersey regulate a title, and the rules differ.
Pennsylvania: Act 144 and the Certified Interior Designer
Pennsylvania Senate Bill 1319 was signed as Act 144 by Governor Josh Shapiro on October 31, 2024, amending the Architects Licensure Law to create a pathway for legal recognition of interior designers. The law creates certification for qualified interior designers and adds a seat for a Certified Interior Designer on the Pennsylvania Board of Architecture. AIA Pennsylvania describes the change. According to Marywood University, the state now requires a four-year degree and certification through the Council for Interior Design Qualification (CIDQ). Act 144 removed earlier barriers that stopped interior designers from being paid for space planning.
New Jersey: the Certified Interior Designer title
New Jersey certifies interior designers through the Interior Design Examination and Evaluation Committee, part of the Division of Consumer Affairs, which sets standards and can discipline certificate holders. A Certified Interior Designer is someone skilled in interior design services for commercial and residential spaces who holds a current, valid certificate from the Board.
The title is protected, the practice is not. The legislation states that it does not prohibit anyone who is not certified from rendering interior design services or calling themselves interior designers, but that person cannot use the title "certified interior designer." Certification requires passing the NCIDQ examination plus a qualifying mix of education and experience. A graduate of a four-year CIDA-accredited program needs at least two years of diversified experience. Certificates renew every two years, and holders must complete 12 continuing education hours per renewal, at least 6 of them on health, safety and welfare. A designer on inactive status may not hold themselves out as a Certified Interior Designer.
You can check a New Jersey certificate through the Division of Consumer Affairs. The Committee's FAQ page lists the fees and renewal rules.
Delaware
Delaware's Division of Professional Regulation licenses architects, and its architect licensing page sets out the requirements for that license. The research for this page found no interior design license or title rule in Delaware.
What this means when you hire
In practice, most designers working in Philadelphia, South Jersey and Wilmington are not certified, and that is legal. Certification tells you the designer met an education and exam standard. It says nothing about whether they are good at your project. Ask what they hold, then look at the work.
What a designer can draw, and when you need an architect
A designer can plan finishes, furniture, lighting layouts, cabinetry and space planning. Structure and the building code are the limit.
Pennsylvania and New Jersey both license architects and protect the title. In Pennsylvania, architect candidates need a professional degree from an accredited program and three years of diversified training through the IDP, and must pass the NCARB Architect Registration Examination. New Jersey requires at least three years in the Architectural Experience Program before an applicant can even sit the exam, and an architectural business such as an LLC must hold a Certificate of Authorization from the State Board of Architects.
In New Jersey, the amendments that created interior design certification specifically removed a provision that would have let code officials accept drawings, schedules and specifications filed by a certified interior designer. A certified designer's drawings do not substitute for an architect's seal on permit documents.
In practice, bring in an architect or engineer when your project removes a bearing wall, adds a beam, changes the exterior envelope or adds square footage. GOLDGCP's in-house architects handle that side, and the structural coordination guide explains how the engineer fits in. For a project that needs stamped drawings for a permit, see permit drawings. For a whole-house job, the additions and remodels guide covers the sequence.
Do you need a permit?
Interior design itself needs no permit. The work it leads to often does, and the answer depends on which state you are in.
Philadelphia
The Department of Licenses and Inspections (L&I) requires a building permit to alter the interior or exterior of a building, but a list of work needs none if the property is not on the Philadelphia Register of Historic Places. That list includes painting and papering, floor coverings, cabinets and countertops, drywall over existing surfaces, and replacing doors and windows in one- and two-family dwellings. Interior non-structural alterations in single-family homes and removing non-load-bearing interior walls can go through an EZ permit without plans, usually approved within 5 business days. The filing fee for a one- or two-family home is $25, and standard review takes 15 business days for alterations. Most projects also need a zoning permit first. Apply in eCLIPSE or at the Permit and License Center at 1401 JFK Blvd.
If the house is on the Philadelphia Register of Historic Places, the Historical Commission must approve any work that requires a building permit or alters the exterior. The Commission has jurisdiction over interiors only when the interior itself is on the Register. Staff approve over 90% of building permit applications without referral to a committee. Call (215) 686-7660 before you order anything.
Suburban Pennsylvania
The Uniform Construction Code applies in Bucks, Chester, Delaware and Montgomery counties, enforced by each township or borough or by a certified third-party agency the owner hires. Pennsylvania's code exempts many like-for-like repairs and alterations that make no structural change, but townships can require permits anyway. Check with the local code office before work starts.
South Jersey
New Jersey's Uniform Construction Code treats painting, wallpaper, window and door replacement in the same opening, cabinets and any flooring material as ordinary maintenance that needs no permit. Cutting a load-bearing wall, structural beams, egress changes and work on water, sewer, gas or vent piping are not ordinary maintenance and do need one. The local enforcing agency must act on a complete application within 20 business days. A designer working in Cherry Hill or elsewhere in South Jersey should know which of your changes need a permit.
Wilmington and New Castle County
New Castle County's Department of Land Use requires a permit for most construction, including interior improvements and alterations, unless the work is on the county's exempt list. The City of Wilmington requires a permit before any work, and projects over $10,000 need a City-licensed general contractor. Check the current thresholds with the city before you sign a contract.
For build costs once the design is set, see the Philadelphia kitchen guide and the bathroom guide.
How long design takes
Schedules depend on scope and on how fast you make decisions. A furnishing-only project skips drawings and permits, so the wait is mostly ordering and delivery. A kitchen or bath with the same layout moves faster than one that moves walls. A remodel that touches structure waits on architect and engineer drawings, then on plan review.
| Project | What sets the pace |
|---|---|
| Furnish or restyle a room | Your decisions, then order and delivery times |
| Kitchen or bath, same layout | Selections, then the city permit |
| Kitchen or bath with wall changes | Floor plans, then plan review |
| Remodel touching structure | Architect and engineer drawings, then plan check |
Changes after drawings are finished cost the most time. Plans may need to go back through review.
How to check an interior designer before you hire
- Ask whether they hold the Pennsylvania certification under Act 144 or the New Jersey Certified Interior Designer title, and ask for the number.
- Look at completed projects in Philadelphia or South Jersey of a similar size and budget.
- Get the fee structure in writing, including any markup, retainer and product deposit.
- Ask who draws anything structural and who pulls permits.
- Ask whether they carry errors and omissions insurance.
- Make sure the contract lists the number of revision rounds and what happens if you cancel.
If the designer also offers to build the project, that counts as construction work. In Pennsylvania, home improvement contractors must register with the Attorney General's Office and put their registration number on contracts and estimates. A home improvement contract over $500 must be in writing with a three-day right to rescind. For contracts over $5,000, a Pennsylvania contractor may not take a deposit of more than one-third of the contract price, or one-third plus the cost of special-order materials named in the contract. In New Jersey, contracts over $500 must be in writing with the contractor's registration number and a three-day right to cancel. In Delaware, the Department of Justice's Home Improvement Services Regulation, effective November 1, 2023, requires a written contract with all material terms and the price filled in before you sign.
For milestone payment practices, see how payment protection works.
Areas we cover
GOLDGCP matches homeowners with interior designers across the Philadelphia metro, including:
- Philadelphia
- The Main Line
- Bucks County
- Delaware County
- Cherry Hill
- South Jersey
- Wilmington
Enter your ZIP code to see design prices for your area and get matched.
How GOLDGCP works
- Tell us about the room or project through the form, a call or WhatsApp.
- You see prices for your ZIP code before anyone visits, and we match you with up to 3 vetted pros.
- Our in-house architects take over the parts that touch structure, permits or an addition.
- You approve each stage and release each milestone payment, and you follow the project in the client portal.
Pros pass six-step vetting before they get a job: state license verification, an insurance check, a background and business check, portfolio review, client reference calls, and onboarding with a quality score. For the trades that follow a design, see our Philadelphia home remodeling guide and electrical guide.
Frequently asked questions
How much does an interior designer cost in Philadelphia?
Hourly rates run $57 to $520. One room costs $520 to $1,700 for design only, or $1,150 to $13,800 with furnishing. A whole 2,000 sq ft home runs $11,500 to $39,100. Furniture, sales tax and any markup are extra.
Do interior designers need a license in Pennsylvania?
No. Pennsylvania does not license interior design practice. Act 144, signed in October 2024, created a certification for qualified interior designers under the Architects Licensure Law. The state now requires a four-year degree and CIDQ certification for it.
What is a Certified Interior Designer in New Jersey?
A designer certified by the New Jersey Division of Consumer Affairs after passing the NCIDQ exam and meeting education and experience requirements. Only certified people may use the title. Uncertified designers can still practice and call themselves interior designers.
Can an interior designer remove a wall in my Philadelphia rowhouse?
They can plan it. If the wall is load bearing, the structural work needs an architect or engineer. Philadelphia L&I requires a building permit for interior alterations, and removing a non-load-bearing wall in a single-family home can go through an EZ permit.
Do I need a permit to redo a kitchen in Philadelphia?
Usually yes for anything beyond cabinets, countertops and finishes. Replacing cabinets and countertops needs no permit if the property is not historic. Moving plumbing or electrical, or changing walls, needs a permit. Most projects also need a zoning permit first.
How do Philadelphia designers charge for furniture?
Usually through cost plus, a percentage added to the net price, or a markup on retail. Product deposits can reach half the furniture cost. Ask how the 8% Philadelphia sales tax is billed and whether markup is calculated before or after it.
Does a designer's drawing work for a New Jersey permit?
No. New Jersey removed the provision that would have let code officials accept drawings filed by a certified interior designer. Permit drawings for structural or code-related work need an architect's seal.
How we calculate these prices
GOLDGCP starts from national price ranges for each job, taken from published 2026 cost guides and checked against local price guides where they exist. To get a local price, we multiply the national range by the construction cost factor for the metro from the U.S. Army Corps of Engineers Area Cost Factors (US average = 1.00). Where that table has no entry for a metro, we use the nearest listed location or the state value. For ZIP codes outside the 50 largest metros, the cost estimator uses the state's price level from the Bureau of Economic Analysis Regional Price Parities. Ranges include labor and standard materials but not unusual site conditions, so a written quote after an inspection is always the final price.
Sources
About this guide
Written by the GOLDGCP editorial team. Prices come from national cost guides adjusted with official construction cost factors for Philadelphia; rules and statistics come from the agencies and reports linked in the text. We update this page when prices or codes change.