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Bath & water guide
Water heaters & water treatment: how to choose
Compare hot-water systems and water-treatment options by household demand, fuel, water quality, installation needs, and ongoing costs.
Decide these first
- Is the current heater failing, undersized, or still repairable?
- What fuel, voltage, venting, and electrical capacity does the home have?
- How many people and simultaneous hot-water uses should the system serve?
- What does a utility or lab water test show about hardness or contaminants?
- What are the installation budget and expected maintenance costs?
Specs that actually matter
Good, better, best
Good
Like-for-like standard tank replacement sized to current demand, with the existing fuel and connections retained.
$881–$1,826 for a typical tank-style replacement.
Better
A correctly sized tankless or hybrid heat-pump unit after checking venting, electrical capacity, and service access.
$1,200–$3,900 for hybrid heat-pump or tankless replacement ranges.
Best
A high-efficiency system selected for peak use, climate, available utilities, controls, and a documented maintenance plan.
$1,200–$3,500 for hybrid heat-pump replacement; upgrades can add cost.
What it costs
| Item | Unit | Typical US range | Source |
|---|---|---|---|
| Tank-style water heater replacement Typical national replacement range; permits, line work, and difficult access can add cost. | each | $881 to $1,826 | Angi 2026 water heater replacement guide |
| Tankless water heater replacement Replacement range; conversion work and venting or electrical upgrades may cost extra. | each | $1,400 to $3,900 | Angi 2026 water heater replacement guide |
| Hybrid heat-pump water heater replacement Replacement range; electrical upgrades and installation conditions affect total cost. | each | $1,200 to $3,500 | Angi 2026 water heater replacement guide |
| Whole-house water treatment system Installed system range; treatment type, capacity, and plumbing changes drive cost. | project | $1,500 to $10,000 | Angi 2026 water treatment system guide |
| Whole-house water softener Installed range for a softener; water quality and household size affect selection. | project | $700 to $3,000 | Angi 2026 water treatment system guide |
| Under-sink water filter installation Typical national installed range; filter type and plumbing complexity affect total. | each | $300 to $1,250 | Angi 2026 under-sink water filter guide |
| Replacement water filter cartridge Replacement media cost; frequency depends on filter type and usage. | each | $15 to $300 | Angi 2026 under-sink water filter guide |
Calculators
Water heater size (first-hour rating)
Size a tank water heater by your busiest hour of hot water use.
Results
Major brands and where to buy
Links go to each manufacturer. Tier is a rough price position, not a quality score.
Retailers
Pitfalls to avoid
- Buying by tank size alone without checking peak demand or recovery needs.
- Overlooking electrical, gas-line, venting, condensate, or clearance requirements.
- Selecting a filter before testing water or identifying the problem to solve.
- Ignoring the cost and schedule for replacement filters, salt, or maintenance.
- Assuming a tankless conversion can reuse existing electrical service and venting.
- Skipping permits, safe venting, or a qualified installer for fuel or electrical work.
What is trending
- Heat-pump water heaters and electrification are shaping product development.
- Leak detection, connected controls, and remote monitoring are increasingly integrated.
- Installers prioritize simpler, more serviceable equipment.
Questions to ask a pro
- What sizing method and peak-use assumptions support the proposed capacity?
- Will my electrical panel, gas line, vent, and condensate route support this model?
- What permits, code upgrades, warranties, and haul-away costs are included?
- What water test or replacement schedule supports the treatment system recommendation?
How long it lasts
Tank-style heaters often last 8–12 years; tankless systems can last 20 years or more with suitable maintenance.
Can you DIY it?
pro-only for water heaters — fuel, electrical, venting, and plumbing connections can create serious safety and code risks.
Permits
Permits and licensed trades are often required for gas, electrical, venting, or plumbing changes; check local code.
Ready to hire?
Get up to 3 quotes from licensed, insured local pros.
Trusted resources
- ENERGY STAR residential water heater criteria Current efficiency and first-hour rating criteria.
- EPA filter guidance for PFAS in drinking water Guidance on home filtration and PFAS.
- PHCPPros 2026 Water Heater Report Manufacturer perspectives on product and installation trends.
From the Journal
Sources
- https://www.angi.com/articles/how-much-does-water-heater-installation-cost.htm
- https://www.angi.com/articles/whole-house-water-filtration-system-cost.htm
- https://www.angi.com/articles/cost-to-install-under-sink-water-filter.htm
- https://www.energystar.gov/products/water_heaters/residential_water_heaters_key_product_criteria
- https://www.phcppros.com/articles/24356-2026-water-heater-report
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