San Antonio ZIP Codes With the Strongest Rental Cash Flow Right Now

If you want cash flow in San Antonio, you are buying south, east, or far-west — not north of 1604. That is the whole story in one sentence. The ZIP codes with the highest rent-to-price ratios in Bexar County sit in the 78220s, 78227, 78228, 78237, 78211, 78221, and across the county line in 78109 (Converse) and 78154 (Schertz starter stock). The ZIP codes people want to own in — 78258 Stone Oak, 78256 The Dominion side, 78230, 78248, 78209 Alamo Heights — are appreciation plays with cash flow that is thin or negative on a typical 25% down conventional loan.

This is a working landlord's map of where the numbers pencil as of recent cycles, what kills the math, and how to pressure-test a specific property before you wire earnest money on a TREC 1-4 contract.

The cash-flow belt: south, east, and near-west

These are the ZIPs where a 3/2 at a realistic acquisition price still produces positive monthly cash flow after full expenses, not just PITI.

• 78223 — southeast, straddling SE Military and Loop 410, Highland Hills and the corridor out toward Brooks. Older inventory, East Central ISD and SAISD depending on street. Blue-collar tenant base, steady demand from Brooks/Port SA employment.
• 78227 — west side off Loop 410 near SeaWorld. Northside ISD on the west edge, which actually helps on rent. 3/2s trade well below the citywide median and rent tighter than the price suggests.
• 78228 — near-west, inside 410. Edgewood and SAISD territory. Small lots, solid 1960s builds, strong demand from service-sector tenants working downtown and the Medical Center.
• 78237 — west side proper, Las Palmas area. Lowest entry prices in the city; highest rent-to-price ratio you will find inside 410. Crime and insurance both higher — underwrite accordingly.
• 78211 — southwest, Southwest ISD. Newer 1980s–2000s tract stock, three-bed rentals that lease in under two weeks in a normal market.
• 78221 — south, Harlandale and SAISD. Closer to downtown than the price implies, which matters for tenants without reliable vehicles.
• 78220 — east side, near AT&T Center and Fort Sam's south gate. Mixed older stock; pockets vary block to block.
• 78109 (Converse) and 78244 — northeast, Judson ISD. Slightly higher entry price than the west side but newer construction, less deferred maintenance, and the Randolph AFB tenant pool.

The common thread: purchase price per door is low enough that rent can cover PITI, tax, insurance, management, vacancy, and capex with room left over. In Stone Oak or Alamo Heights, rent cannot do that at current prices without 40%+ down.

Why the north side doesn't cash flow

78258, 78259, 78260, 78248, 78256, 78230 — these are appreciation markets. A $450K 3/2 in Stone Oak rents for roughly the same as a $240K 3/2 in 78227, because the tenant pool for $3,000/month SFR rentals in San Antonio is thinner than people assume. The rent-to-price ratio collapses. You are paying for NEISD and NISD schools, for HOA-maintained curb appeal, and for the belief that the home will be worth meaningfully more in seven years. That may be true. It is not cash flow.

If your strategy is 1031 appreciation and you have W-2 income to absorb paper losses, north-side SFR makes sense. If you need the property to feed itself from month one, stop looking there.

The two numbers that kill spreadsheets

Two line items sink more San Antonio rental pro-formas than any other, and both are locally specific.

Property tax

Bexar County total property tax rates routinely land in the 2.3%–2.9% range depending on ISD, city, and special districts. A home in SAISD inside the City of San Antonio is taxed differently than the same home in Judson ISD inside Converse. You can pull the exact rate for any parcel from BCAD's property search — do that before you offer, not after. And remember: you do not get the homestead exemption on a rental. The § 11.13 exemption and its 10% assessed-value cap apply to an owner-occupied primary residence. Rentals are reappraised to market every year with no cap. New investors plug last year's tax bill into their model; BCAD hits them with a 25% bump the January after closing.

Insurance

Texas landlord (DP-3) policies have climbed hard. Wind/hail deductibles in Bexar County are often 1%–2% of dwelling coverage, separately stated. Older west-side stock with original electrical or a 20-year-old roof will either get non-renewed or quoted at a premium that eats your cash flow. Get a real quote — not an estimate — on a specific address before you remove your option under the TREC 1-4.

How to pressure-test a ZIP in 20 minutes

Before you fall in love with a neighborhood:

1. Pull 10 recent leases on SABOR MLS for the ZIP, same bed/bath, last 90 days. Median leased rent, not list rent. Days on market matters more than dollar number — if median DOM is over 30, the market is soft.
2. Pull the last 10 sold comps same bed/bath. Calculate rent ÷ price. Anything under 0.6% monthly is an appreciation play, not a cash-flow play. Over 0.8% is genuinely strong for an SFR.
3. Look up the tax rate for a specific nearby parcel on BCAD. Multiply by your expected purchase price. That is year-two tax, not year-one.
4. Quote insurance for the exact address with a broker who writes DP-3 in Bexar County.
5. Check the JP precinct — Bexar County has four JP precincts handling evictions, and they differ in docket speed and landlord-friendliness. Know which one your address sits in before you buy.

What most people get wrong

• Using the purchase-price tax bill in the pro-forma. BCAD reassesses to sale price. Budget year-two taxes at 2.5%+ of purchase price from day one.
• Mixing up NEISD and NISD. Northeast ISD covers 78209, 78217, 78247, 78258. Northside ISD covers the west and far-northwest — 78227, 78229, 78230, 78250, 78251, 78254, 78256. Tenants ask about schools by district name. Get it right in the listing.
• Trusting online rent estimates. They pull from list prices and national models. Use SABOR leased comps or pay a local property manager for a 15-minute rent opinion.
• Buying 78237 without walking the block at 9 p.m. Rent-to-price looks incredible on paper. Tenant quality and turnover cost are the real variables. The spreadsheet that assumes 8% vacancy gets 20% vacancy in practice on the wrong block.
• Ignoring repair duty under § 92.052. Older west/south-side stock means more habitability calls — HVAC, plumbing, roof leaks. The Property Code does not care that you bought cheap. Budget real capex, not 5% of rent.
• Skipping the flood map. Large parts of 78220, 78223, and pockets of 78227 touch Salado Creek, Rosillo Creek, or Leon Creek floodplains. A Special Flood Hazard Area designation adds flood insurance and changes the loan.

Cash flow vs. blended strategy

Most landlords who scale past five doors in Bexar County run a blend: two or three cash-flow properties in the 78220s / 78227 / 78109 carrying the portfolio, one or two appreciation holds on the north side or in Boerne ETJ for long-term equity. Pure cash-flow portfolios work until a roof and an HVAC fail in the same quarter. Pure appreciation portfolios work until you need the properties to survive a six-month vacancy.

Whatever the mix, the acquisition math is the same: real BCAD tax, real DP-3 insurance quote, real SABOR-comped rent, realistic capex reserve. Anything else is a hobby.

When you are ready to underwrite specific addresses, RentInSA's rental inventory at /rentals shows what is actually leasing — and at what rent — across these ZIPs in real time. If you're building a portfolio and want a landlord-side agent who underwrites before they show, /agents is where to start. More market breakdowns live under /resources.