Phosphorus test cost in Boston, MA
In Boston-Cambridge-Newton, MA-NH, 26 hospitals list a cash price for phosphorus (phosphate) blood test: from $7.94 to $205.00, with a median of $39.00. The lowest listed price is at Boston Medical Center South — $31.06 less than the median here. Across Massachusetts, the median is $26.00 at 33 hospitals.
Cash prices at 26 facilities across 19 cities for code 84100, as an outpatient — the setting a self-pay patient normally buys. Collected Sep 29, 2026; the hospital files themselves were last updated between Jan 28, 2026 and Sep 1, 2026.
Where each hospital's price falls
Each dot is one hospital's cash price on a scale from the lowest to the highest in Boston-Cambridge-Newton, MA-NH.
Hospitals, cheapest first
| Hospital | Cash price | List price | Insurers pay | Off list | File date |
|---|---|---|---|---|---|
| Boston Medical Center South lowest Brockton, MA · (508) 427-3000 HC Chg Assay of Phosphorus Inorganic | $7.94 | $17.65 | $4.18–$394.86 | 55% | — source file |
| Boston Medical Center Brighton Boston, MA · (617) 789-3000 HC Chg Assay of Phosphorus Inorganic | $9.03 | $20.07 | $4.18–$475.07 | 55% | — source file |
| Tufts Medical Center Boston, MA · (617) 636-5000 HC Assay of Inorganic Phosphorus - Phosphorus Body | $11.90 | $17.00 | $4.46–$20.58 | 30% | — source file |
| Lowell General Hospital Lowell, MA · (978) 937-6000 HC Assay of Inorganic Phosphorus - Phosphorus Body | $11.90 | $17.00 | $5.95–$19.48 | 30% | — source file |
| Melrosewakefield Healthcare Melrose, MA · (781) 979-3000 HC Assay of Inorganic Phosphorus - Phosphorus Body | $11.90 | $17.00 | $5.95–$530.75 | 30% | — source file |
| Signature Healthcare Brockton Hospital Brockton, MA · (508) 941-7000 PHOSPHORUS LEVEL | $14.00 | $20.00 | $4.65–$15.19 | 30% | Jan 28, 2026 source file |
| Beth Israel Deaconess Hospital - Plymouth Plymouth, MA · (508) 746-2000 CHG ASSAY OF PHOSPHORUS INORGANIC | $20.00 | $20.00 | — | — | Apr 1, 2026 source file |
| Emerson Hospital Concord, MA · (978) 369-1400 PHOSPHOROUS | $20.25 | $27.00 | $4.50–$27.00 | 25% | May 18, 2026 source file |
| Emerson Hospital Concord, MA · (978) 369-1400 ASSAY OF PHOSPHORUS | $20.25 | $27.00 | $4.50–$27.00 | 25% | May 18, 2026 source file |
| Southcoast Hospitals Group - Tobey Hospital Campus Wareham, MA · (508) 679-3131 HC Assay of Inorganic Phosphorus | $21.00 | $42.00 | $4.74–$31.96 | 50% | — source file |
| Boston Medical Center Boston, MA · (617) 638-8000 HC Chg Assay of Phosphorus Inorganic | $22.50 | $50.00 | $4.10–$512.54 | 55% | — source file |
| Cambridge Health Alliance Cambridge, MA · (617) 665-1000 HC Phosphorus | $26.00 | $26.00 | $4.18–$32.73 | — | — source file |
| Beth Israel Deaconess Hospital-Milton Milton, MA · (617) 696-4600 CHG ASSAY OF PHOSPHORUS INORGANIC | $32.00 | $32.00 | — | — | Apr 1, 2026 source file |
| Mount Auburn Hospital Cambridge, MA · (617) 492-3500 CHG ASSAY OF PHOSPHORUS INORGANIC | $35.00 | $35.00 | — | — | Apr 1, 2026 source file |
| Beth Israel Deaconess Hospital - Needham Needham, MA · (781) 453-3002 CHG ASSAY OF PHOSPHORUS INORGANIC | $43.00 | $43.00 | — | — | Apr 1, 2026 source file |
| Shriners Childrens - Boston Boston, MA · (617) 722-3000 PHOSPHATE LEVEL | $45.90 | $45.90 | $4.10–$817.41 | — | — source file |
| Beth Israel Deaconess Medical Center Boston, MA · (617) 667-7000 CHG ASSAY OF PHOSPHORUS INORGANIC | $58.00 | $58.00 | — | — | Apr 1, 2026 source file |
| New England Baptist Hospital Boston, MA · (617) 754-5800 CHG ASSAY OF PHOSPHORUS INORGANIC | $64.00 | $64.00 | — | — | Apr 1, 2026 source file |
| Lahey Hospital & Medical Center, Burlington Burlington, MA · (781) 744-5100 CHG ASSAY OF PHOSPHORUS INORGANIC | $75.00 | $75.00 | — | — | Apr 1, 2026 source file |
| Anna Jaques Hospital Newburyport, MA · (978) 463-1000 CHG ASSAY OF PHOSPHORUS INORGANIC | $78.00 | $78.00 | — | — | Apr 1, 2026 source file |
| Winchester Hospital Winchester, MA · (781) 729-9000 CHG ASSAY OF PHOSPHORUS INORGANIC | $102.00 | $102.00 | — | — | Apr 1, 2026 source file |
| Exeter Hospital Exeter, NH · (603) 778-7311 CHG ASSAY OF PHOSPHORUS INORGANIC | $109.00 | $109.00 | — | — | Apr 1, 2026 source file |
| Seabrook Emergency Seabrook, NH · (603) 436-5110 PHOSPHORUS BLD | $134.00 | $134.00 | $34.44–$127.30 | — | Sep 1, 2026 source file |
| Portsmouth Regional Hospital Portsmouth, NH · (603) 436-5110 Phosphorus inorganic (phosphate); | $134.00 | $134.00 | $8.17–$19.10 | — | Sep 1, 2026 source file |
| Portsmouth Regional Hospital Portsmouth, NH · (603) 436-5110 PHOSPHORUS BLD | $134.00 | $134.00 | $34.44–$127.30 | — | Sep 1, 2026 source file |
| Dover Emergency Room Dover, NH · (603) 436-5110 PHOSPHORUS BLD | $134.00 | $134.00 | $34.44–$127.30 | — | Sep 1, 2026 source file |
| Dover Emergency Room Dover, NH · (603) 436-5110 Phosphorus inorganic (phosphate); | $134.00 | $134.00 | $8.17–$19.10 | — | Sep 1, 2026 source file |
| Seabrook Emergency Seabrook, NH · (603) 436-5110 Phosphorus inorganic (phosphate); | $134.00 | $134.00 | $8.17–$19.10 | — | Sep 1, 2026 source file |
| Parkland Medical Center Derry, NH · (603) 421-2100 Phosphorus inorganic (phosphate); | $205.00 | $205.00 | $7.80–$19.27 | — | Sep 1, 2026 source file |
| Plaistow Fser Plaistow, NH · (603) 421-2100 PHOSPHORUS BLD | $205.00 | $205.00 | $43.05–$194.75 | — | Sep 1, 2026 source file |
| Plaistow Fser Plaistow, NH · (603) 421-2100 Phosphorus inorganic (phosphate); | $205.00 | $205.00 | $7.80–$19.27 | — | Sep 1, 2026 source file |
| Parkland Medical Center Derry, NH · (603) 421-2100 PHOSPHORUS BLD | $205.00 | $205.00 | $43.05–$194.75 | — | Sep 1, 2026 source file |
Outpatient: lowest $7.94, median $39.00, highest $205.00 — a 25.8× difference within the same market.
As an inpatient, the same code is billed by 21 facilities here, median $26.00. Inpatient and outpatient prices are not comparable and are kept on separate pages: the inpatient charge covers admission, not the same purchase.
Cash or insurance?
At 11 of 16 hospitals that publish insurer rates for this code here, the cash price is below the highest rate a health plan has negotiated, and at none is it below every plan's rate. If you have insurance but have not met your deductible, you usually pay your plan's negotiated rate, which falls somewhere in the "Insurers pay" column. Paying cash can cost less, but a cash payment usually does not count toward your deductible. Ask the hospital for both numbers before you book.
What it is
A phosphorus test measures phosphate in the blood. It is used with calcium for kidney disease, bone disease and parathyroid problems.
What the price covers
The price usually covers running the test. The blood draw (36415) is often billed as a separate line.