Onyx vanity top prices typically range from $700 to $3,500 installed, with many standard bathroom projects landing near $1,600. The final quote depends on top size, slab thickness and grade, sink and faucet cutouts, edge finishing, installation labor, and whether an existing counter must be removed.
| Item | Low | Average | High | Notes |
|---|---|---|---|---|
| Installed vanity top | $700 | $1,600 | $3,500 | Typical 30-72-inch bathroom top |
| Onyx material | $40 per sq ft | $90 per sq ft | $200 per sq ft | Price varies by color, grade, and slab source |
| Fabrication | $250 | $600 | $1,300 | Includes shaping, cutouts, and finishing |
| Installation labor | $200 | $450 | $900 | More for heavy, awkward, or complex installs |
| Removal and disposal | $75 | $200 | $450 | Often quoted separately |
Assumptions: U.S. prices for a standard bathroom vanity, ordinary access, and professional fabrication; plumbing fixtures may be additional.
How Much Does an Onyx Vanity Top Cost by Size?
A small 24-30-inch onyx vanity top often costs $700-$1,400 installed. A common 36-48-inch top usually falls around $1,000-$2,200, while a 60-72-inch double-sink top can reach $1,800-$3,500 or more. These ranges assume a straightforward rectangular shape, standard polished finish, and ordinary installation access.
Onyx slab pricing is often quoted at roughly $40-$200 per square foot for the stone itself. A modest top may use only 4-6 square feet, but the shop must account for usable slab area, veining, waste, and the ability to match patterns. A small custom order can therefore cost more per square foot than its dimensions suggest.
For a typical 36-inch bathroom vanity, a practical installed budget is about $1,000-$2,200 before premium sinks, plumbing changes, or unusual site work. Price estimates should specify whether the quote includes the sink, faucet holes, backsplash, tax, delivery, and removal of the old top.
Some quotes describe the stone as a “vanity top” package, while others price the slab, fabrication, and installation separately. Comparing total installed prices is more useful than comparing slab rates alone, especially when one bid includes a sink and backsplash and another does not.
Where Onyx Slab, Fabrication, and Labor Appear in the Quote
The stone is only one part of the bill. Fabricators measure the cabinet, select and cut the material, finish exposed edges, create openings, and prepare the piece for transport. Installers then set and secure the top, align it with the vanity, and make needed connections or adjustments within the agreed scope.
| Quote component | Low | Typical | High | What changes the charge |
|---|---|---|---|---|
| Onyx material | $160 | $450-$900 | $1,400 | Size, color, grade, and slab waste |
| Fabrication and edge work | $250 | $450-$850 | $1,300 | Cutouts, seams, and shaped edges |
| Labor and setting | $200 | $350-$600 | $900 | Access, handling, and installation complexity |
| Equipment and delivery | $50 | $125-$300 | $500 | Travel distance, stairs, and lifting needs |
| Permits and disposal | $0 | $75-$200 | $450 | Local rules and old-top removal |
Labor may be estimated as a flat installation charge or based on crew time. For an uncomplicated replacement, installation labor commonly runs $200-$600; a two-person crew may spend 2-5 hours on site, not including shop fabrication.
A quote should separate stone, shop work, delivery, installation, and removal so the total can be checked line by line. The table’s components are planning ranges, not amounts that should automatically be added at their maximum; some businesses bundle delivery or labor into a package price.
Why Slab Thickness, Sink Cuts, and Edge Profiles Change Price
Thickness affects both material use and handling. A standard 3/4-inch slab may be less expensive than a 1 1/4-inch or built-up edge, although the finished appearance and support requirements also matter. Ask whether the quoted thickness is the actual stone thickness or a laminated edge that creates a thicker look.
Sink openings are another important variable. One undermount sink cutout may add about $100-$300, depending on edge finishing and shop requirements. A double vanity with two sink cutouts can add $200-$600. Faucet holes may be included, but extra holes or unusual spacing can add roughly $25-$75 each.
Simple eased or pencil edges are generally less costly than decorative profiles. A basic edge may be included or add $10-$25 per linear foot; a more detailed profile can add $25-$60 per linear foot. Curved fronts, waterfall returns, and shaped corners require more cutting and polishing than a standard straight front.
Onyx’s natural patterns can also affect yield. Matching dramatic veins across a long 60-inch top or around a seam may require more material selection and careful layout. If a usable slab has a flaw or the desired pattern runs in a particular direction, a fabricator may need a larger remnant or additional slab area.
Cutouts and finished edges can add several hundred dollars even when the vanity itself is small. The estimate should list the number and type of sink openings, faucet holes, exposed edges, backsplash dimensions, and any requested vein matching.
Can a Smaller Vanity or Remnant Lower the Onyx Price?
Choosing a 24-36-inch top instead of a 60-inch double-sink design reduces the stone area and usually limits the number of cutouts. The savings are not always proportional to square footage because measurement, fabrication setup, delivery, and installation still create minimum charges. A small custom top can carry a higher per-square-foot rate than a larger one.
A remnant can reduce material cost when it is large enough and has a suitable color, thickness, and pattern. Remnant material may be priced 15%-40% below comparable full-slab pricing, but availability is unpredictable. It may not be practical for a long vanity, a matched backsplash, or a project requiring consistent veining across multiple pieces.
Standard rectangular dimensions and a simple edge are generally more economical than custom curves, multiple seams, or elaborate profiles. Keeping the existing cabinet and plumbing locations also avoids extra carpentry or plumbing work. Changing a sink position can require cabinet alterations and new drain or supply connections, which may add $150-$600 or more.
The most reliable savings usually come from reducing fabrication complexity rather than choosing the cheapest-looking stone alone. Before approving a remnant or smaller piece, confirm the finished dimensions, cutout locations, visible flaws, and what happens if the stone breaks during fabrication or installation.
Regional Onyx Installation Rates Across U.S. Markets
Labor and delivery can make the same onyx top cost more in a high-cost metro than in a smaller market. As a planning estimate, dense urban areas in the Northeast, West Coast, and major coastal metros may run 10%-25% above the national middle range. Smaller cities and rural markets may come in 5%-15% below it, although limited fabricator availability can offset that difference.
In higher-cost markets, a standard installed 36-inch top may be closer to $1,300-$2,500; in lower-cost regions, a similar project may be nearer $900-$1,900. These are broad comparisons, not fixed regional prices. Local stone supply, contractor schedules, building access, and the distance from the fabricator can shift the estimate substantially.
Delivery deserves special attention in dense buildings. Stairs, narrow hallways, elevator reservations, parking restrictions, and long carries can add $75-$400 or more. Rural addresses may face mileage or minimum-trip fees, sometimes $50-$250 depending on distance and company policy.
Regional price comparisons are most useful when the scope is identical and delivery and removal are included in both quotes. A local installer’s estimate should note whether the price includes measuring, transport, setting materials, and a return trip for adjustments.
How Long Onyx Countertop Fabrication and Installation Take
After final measurements and material selection, fabrication commonly takes 1-3 weeks. Special-order colors, slab transfers, detailed edge work, or a busy shop can stretch the wait to 3-6 weeks. The installation itself usually takes 2-5 hours for a straightforward single vanity and may require a two-person crew because the stone must be handled carefully.
For a replacement, removal of the existing top can take 1-3 hours, with additional time if it is bonded heavily, tiled into the wall, or attached to a damaged cabinet. The vanity may need to remain out of service until the new top is set and plumbing is reconnected. A separate plumber may charge $100-$250 for basic fixture disconnection and reconnection, depending on local rates and complications.
Scheduling may affect price when a project requires a rush slot, weekend work, or a narrow building-access window. Rush fabrication can add roughly 10%-25% where available, and special delivery arrangements may add $75-$300. These charges are not universal, so the written estimate should identify any expedited fee.
Allow several weeks for a custom top, even though the actual on-site installation may take only part of a day. Confirm that the shop has completed final measurements before cutting; cabinet walls and finished surfaces can differ from preliminary dimensions.
Sink, Backsplash, and Tear-Out Charges to Budget For
A vanity top package may include an integral or undermount sink, but the sink style and brand can change the total. A basic compatible sink may add $75-$250, while a higher-end basin may cost $250-$700 or more. Sink installation or mounting hardware can be separate, so the quote should state whether the basin is supplied and attached by the fabricator.
A short stone backsplash, often 3-4 inches high, may add $75-$250 for a straightforward piece. A full-height backsplash or side splash may cost $150-$500 or more depending on length, thickness, matching requirements, and the number of finished edges. Tile removal or wall repair can create additional costs if the new stone does not cover the prior footprint.
Removing an old laminate or cultured-marble top commonly costs $75-$250, including basic disposal. Stone removal may cost $200-$450 because it is heavier and can require extra labor. Plumbing disconnection, cabinet repairs, and wall patching are often outside a countertop installer’s base price.
Onyx requires care during transport and handling because it can be more fragile than some common countertop materials. A fabricator may charge for a support substrate or special handling based on the slab and installation design. Ask what the price includes if a piece cracks before setting, and whether the warranty covers installation or only workmanship.
Confirm sink, backsplash, tear-out, plumbing, and wall repair as separate line items before comparing totals. A low base quote may exclude these tasks, while a higher bundled estimate may include them.
Onyx Versus Quartz and Marble for a Bathroom Vanity
Onyx is typically chosen for its translucent appearance and distinctive natural veining, but it is often a higher-maintenance choice than engineered quartz. A standard quartz vanity top commonly costs about $800-$2,500 installed, depending on size and fabrication. Marble often falls around $900-$3,000 installed for bathroom-sized projects, with premium stone and custom work exceeding that range.
Quartz usually offers more uniform patterns and does not require the same sealing routine as many natural stones. Marble and onyx are natural stones, so their appearance varies from slab to slab and they may need periodic sealing. For any material, confirm the manufacturer’s care instructions and warranty terms; staining, etching, impact damage, and installation defects may be treated differently.
A laminate or solid-surface top can be a lower-cost alternative when the goal is a practical vanity rather than a specific natural-stone look. Basic alternatives may run roughly $200-$1,000 installed, depending on the size and whether the sink is integrated. Replacing only a damaged sink or repairing a loose seam may cost less than replacing a whole top, but a repair may not blend with a patterned stone surface.
Compare the installed price and expected care, not just the slab price, when weighing onyx against quartz or marble. For a valid comparison, use the same vanity dimensions, sink configuration, backsplash scope, edge finish, and removal assumptions for each material.