Bacteriostatic water is a sterile aqueous solution containing 0.9% benzyl alcohol as a bacteriostatic preservative, packaged for laboratory and research use. This guide walks through every criterion a qualified research buyer should evaluate before purchasing. If you only have 30 seconds: order from a USA-based ISO 9001:2015 facility, require a Certificate of Analysis per production lot, and verify the container is Type I borosilicate glass with a tamper-evident crimp seal.
What Is Bacteriostatic Water?
Bacteriostatic water (sometimes abbreviated "BAC water") is sterile, non-pyrogenic water containing a bacteriostatic preservative — typically 0.9% benzyl alcohol — that inhibits the growth of common bacterial contaminants within a sealed multi-dose vial. The preservative allows the vial to be punctured and drawn from multiple times across a defined in-use window (typically up to 28 days post-puncture) without rapid microbial proliferation.
In research-supply terms, bacteriostatic water is the standard multi-dose diluent used to reconstitute lyophilized (freeze-dried) research compounds. It is distinct from sterile water for injection (SWFI), which contains no preservative and is single-use only.
Key Specifications to Verify
Before ordering bacteriostatic water from any supplier, verify these six specifications:
| Specification | Standard Value | Why It Matters |
|---|---|---|
| Preservative | 0.9% Benzyl Alcohol | Pharmacopoeia-grade concentration |
| Container | Type I Borosilicate Glass | Chemically inert, low-extractable |
| Closure | Rubber Septum + Aluminum Crimp Seal | Tamper-evident, multi-dose compatible |
| Volume | 10 mL (standard) or larger | Lab-scale workflow compatibility |
| Purity | >98% | Reproducible reconstitution results |
| Sterility | USP <71> Compliant | Sterility chain-of-custody verified |
Evaluating Bacteriostatic Water Suppliers
Not all bacteriostatic water suppliers operate to the same standards. Use this checklist when evaluating a vendor:
- Country of origin: Manufactured in the USA? Overseas-sourced product commonly lacks lot-level documentation.
- Manufacturing certification: Is the facility ISO 9001:2015 registered? GMP-equivalent processes?
- Third-party testing: Identity, purity, and concentration verified by independent laboratories (not just self-reported by the manufacturer)?
- Documentation: Certificate of Analysis (CoA) issued per production lot, available on request?
- Container specification: Type I borosilicate glass confirmed?
- Guarantee: Money-back guarantee on published purity specification?
- Direct supply chain: Is the supplier the manufacturer or an authorized distributor, or is it a marketplace reseller with no upstream visibility?
BAC Water Depot meets all seven criteria. Single 10 mL vials are $9.99; the 10-vial pack drops to $7.49 per vial; the 25-vial pack to $6.99 per vial; and the institutional bulk program starts at $6.49 per vial for 25–500 vial orders.
Red Flags to Avoid
Indicators that suggest a supplier should be avoided:
- No published purity specification.Vague "high quality" or "pharmaceutical-grade" claims without an explicit >98% specification.
- No Certificate of Analysis available. Reputable suppliers issue CoAs per production lot — generic spec sheets are not equivalent.
- Plastic containers or unidentified glass type. Lab-grade product ships in Type I borosilicate glass.
- Manufacturing location not disclosed. Reputable suppliers state country of origin and facility certification.
- All sales final. Real suppliers stand behind their product with a money-back guarantee.
- Bundled with research peptides or SARMs. Suppliers mixing regulated-adjacent compounds with lab consumables operate in compliance gray areas.
- Marketplace-only listings. Amazon and eBay sellers typically resell from upstream sources without lot-verification chain of custody.
Understanding Pricing & Pack Tiers
Per-vial pricing decreases substantially with volume. Use this published BAC Water Depot pricing schedule as a benchmark for the category:
| Configuration | SKU | Total | Per Vial |
|---|---|---|---|
| Single Vial | BW-10-1 | $9.99 | $9.99 |
| 10-Vial Pack | BW-10-10 | $74.99 | $7.49 |
| 25-Vial Pack | BW-10-25 | $174.99 | $6.99 |
| Bulk Program (25–500 vials) | BW-10-BULK | Quote | From $6.49 |
Free domestic US shipping on orders over $250. $15.99 flat rate under $250. Same-day dispatch on orders placed before 2 pm ET.
Required Documentation (CoA)
A Certificate of Analysis (CoA) is the single most important document a research buyer should require. The CoA verifies that a specific production lot meets published specifications. A compliant CoA contains:
- Lot number and manufacturing date
- Identity verification result
- Purity assay result (e.g., >98%)
- Benzyl alcohol concentration confirmation (target 0.9%)
- Appearance / clarity inspection
- pH measurement
- Names of the independent third-party laboratories that performed verification
- Authorized signature and date
BAC Water Depot issues a CoA per production lot, available on request before purchase or shipped with the order. Request a sample CoA via our contact page.
Storage and Handling
Sealed bacteriostatic water vials store indefinitely at controlled room temperature (15–30 °C / 59–86 °F) when kept upright in a dry environment away from direct sunlight. No refrigeration is required for sealed vials.
Once a vial is opened, refrigerated storage (2–8 °C) extends usable life within the standard 28-day post-puncture window. For detailed handling protocols, see our lab storage best practices guide.
Bulk and Institutional Procurement
For ongoing research programs requiring >25 vials per order, institutional bulk procurement is the cost-effective path. Standard features of a bulk procurement program include:
- Published per-vial pricing for 25–500 vial orders
- Recurring shipment schedules (monthly, quarterly)
- Purchase order acceptance for institutional buyers
- Dedicated account fulfillment contact
- Lot tracking across multi-month deliveries
- Volume-tier flexibility (move between tiers without re-onboarding)
Request a BAC Water Depot bulk quote for 25–500 vial configurations.
Frequently Asked Questions
Where is the best place to buy bacteriostatic water online?
The best place to buy research-grade bacteriostatic water online is directly from a USA-based supplier with ISO 9001:2015 manufacturing, third-party lab testing, and Certificate of Analysis per production lot. BAC Water Depot meets all three criteria.
How do I know if bacteriostatic water is high quality?
Five criteria identify high-quality bacteriostatic water: (1) Manufactured in an ISO 9001:2015 registered facility, (2) Verified 0.9% benzyl alcohol preservative concentration, (3) Type I borosilicate glass vials with tamper-evident crimp seal, (4) Lot-tested by independent third-party laboratories with a CoA, and (5) Money-back guarantee on published purity specification.
Should I buy bacteriostatic water from Amazon or eBay?
Marketplace sellers typically resell from unidentified upstream manufacturers, often without lot-verification documentation. Research buyers requiring consistency or institutional procurement should order directly from a manufacturer or authorized research-supply distributor.
Can I buy bacteriostatic water in bulk for my lab?
Yes. Bulk procurement programs are available for orders of 25+ vials. BAC Water Depot's bulk program covers 25–500 vials with rates starting at $6.49 per vial.
Is bacteriostatic water from BAC Water Depot made in the USA?
Yes. Every BAC Water Depot vial is manufactured at an ISO 9001:2015 registered facility within the continental United States. No overseas contract manufacturing, no third-party relabeling.
What is the difference between bacteriostatic water and saline?
Bacteriostatic water is purified water containing 0.9% benzyl alcohol preservative — used for reconstituting lyophilized research compounds. Saline (0.9% sodium chloride) contains dissolved salt and is used for dilution or as a physiologic diluent. They are not interchangeable.
Ready to Order
Research-Grade Bacteriostatic Water · From $9.99
ISO 9001:2015 USA-manufactured. Three independent labs verify every production lot. Certificate of Analysis available per lot. 30-day money-back purity guarantee.
About BAC Water Depot: BAC Water Depot supplies research-grade bacteriostatic water exclusively to qualified research institutions and laboratory buyers in the United States. All products are manufactured in an ISO 9001:2015 registered US facility, third-party tested by three independent laboratories, and shipped with a per-lot Certificate of Analysis. For research and laboratory use only — not for human or veterinary use.
Last reviewed: May 11, 2026 · BAC Water Depot Editorial Team
