Tides Today & Tomorrow in Boston, MA

TIDE TIMES for Saturday, July 18, 2026
The tide is currently falling in Boston, MA.
Next low tide : in 4h 10m at 8:57 am (-0.5 ft)
Next high tide : 3:15 pm (10.3 ft)
Sunset today : 8:17 pm
Sunrise tomorrow : 5:23 am
Moon phase : Waxing Crescent (23% illuminated)
Tide Station Location : Station #8443970
Common Questions About Tides

Boston, MA Tides - Sep 2077

DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
1Wed10:399.610:5311.34:28-0.34:410.26:107:17Full Moon1Wed
2Thu11:2910.311:4511.65:18-0.85:33-0.46:117:15Full Moon2Thu
3Fri12:1810.86:07-1.16:25-0.86:127:13Full Moon3Fri
4Sat12:3711.71:0711.26:55-1.37:17-1.16:137:12Waning Gibbous4Sat
5Sun1:3011.61:5711.47:44-1.28:10-1.26:147:10Waning Gibbous5Sun
6Mon2:2311.32:4711.48:33-0.99:04-1.06:157:08Waning Gibbous6Mon
7Tue3:1710.73:3911.29:24-0.410:00-0.66:167:06Third Quarter7Tue
8Wed4:1510.14:3510.810:180.311:00-0.16:177:05Third Quarter8Wed
9Thu5:169.55:3510.411:160.96:187:03Third Quarter9Thu
10Fri6:219.06:3810.012:020.312:171.36:197:01Third Quarter10Fri
11Sat7:278.77:439.81:070.61:191.66:206:59Waning Crescent11Sat
12Sun8:338.78:469.72:120.82:221.76:216:58Waning Crescent12Sun
13Mon9:328.89:439.83:140.83:221.66:226:56Waning Crescent13Mon
14Tue10:229.010:329.94:070.74:141.46:236:54Waning Crescent14Tue
15Wed11:049.211:1410.04:510.64:591.16:246:52New Moon15Wed
16Thu11:429.411:5310.05:290.65:390.96:256:51New Moon16Thu
17Fri12:179.66:050.66:180.86:266:49New Moon17Fri
18Sat12:319.912:519.76:400.66:560.76:286:47New Moon18Sat
19Sun1:089.81:259.87:150.77:340.76:296:45Waxing Crescent19Sun
20Mon1:469.62:009.77:510.98:130.76:306:44Waxing Crescent20Mon
21Tue2:249.32:369.78:271.28:530.96:316:42Waxing Crescent21Tue
22Wed3:049.03:159.69:061.59:361.16:326:40Waxing Crescent22Wed
23Thu3:478.73:579.59:481.810:231.26:336:38First Quarter23Thu
24Fri4:358.44:459.410:352.011:161.36:346:36First Quarter24Fri
25Sat5:288.25:399.411:292.16:356:35First Quarter25Sat
26Sun6:258.26:389.612:131.312:262.16:366:33First Quarter26Sun
27Mon7:258.47:389.91:111.11:261.86:376:31Waxing Gibbous27Mon
28Tue8:248.98:3910.32:100.72:271.36:386:29Waxing Gibbous28Tue
29Wed9:219.59:3810.83:080.23:250.66:396:28Waxing Gibbous29Wed
30Thu10:1310.310:3311.24:01-0.44:21-0.26:406:26Full Moon30Thu
DateHigh TideLow TideSunMoonDate
AMftPMftAMftPMftRiseSet
Tidal Data Source: (8443970)

Common Questions About Boston, MA Tides

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What time does the tide turn (slack tide) in Boston, MA today?

Slack tide in Boston, MA is approximately 12:06 pm — midway between the next high and low tide, when tidal current is weakest. This is the preferred window for boat crossings, underwater visibility, and fishing in areas with strong currents.

Is this week a spring tide or neap tide in Boston, MA?

Boston, MA is currently in a transitional phase. Tonight's moon is 23% illuminated. Spring tides (largest swings) occur near new and full moons; neap tides (smallest swings) occur near first and third quarter moons. Tidal ranges this week are shifting between spring and neap.

What datum are Boston, MA tide heights measured from?

Tide heights on this page are measured from Mean Lower Low Water (MLLW), the U.S. NOAA standard. A height of 0 ft represents the 19-year average of each day's lower low tide. Negative values indicate a "minus tide" — water levels below that long-term reference.

What factors can affect the tide predictions for Boston, MA?

Tide predictions for Boston, MA come from NOAA's harmonic analysis and are typically accurate within about ±10 minutes on timing and ±0.5 ft on height. Actual water levels can deviate further due to sustained winds, atmospheric pressure changes, river flow, and storm surge. During major weather events, be sure to check US Harbors weather pages for factors that could impact tidal predictions.

Which NOAA station provides tide data for Boston, MA?

Tide data for Boston, MA is sourced from NOAA Station #8443970. View the official NOAA station page at https://tidesandcurrents.noaa.gov/stationhome.html?id=8443970.

What is the moon phase in Boston, MA tonight?

Tonight the moon over Boston, MA is Waxing Crescent (23% illuminated). This places Boston, MA in a transitional tide cycle, so tidal ranges are shifting between spring and neap this week.

US Harbors Tidal Data

The data in our tide charts, tide tables, and tide graphs is provided by NOAA and others. These predictions are derived mathematically from numerous inputs, including data from historical tide stations and nearby locations where sensors are actively recording. As shown in the tide graph at the top of this page, “Predicted” tides (blue) are what forecasting models expect to happen. “Observed” tides (red) are those recorded by local sensors in real time, overlaid on the predictions for direct comparison. We display Observed water levels for a select group of harbors including Portland, Maine, where a physical sensor monitors water levels in real time.

LEARN MORE ABOUT OUR TIDE DATA